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</div> <div class="control"> <button class="button is-small is-link">Go</button> </div> </div> </form> </div> </div> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> </ul> </nav> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2409.11347">arXiv:2409.11347</a> <span> [<a href="https://arxiv.org/pdf/2409.11347">pdf</a>, <a href="https://arxiv.org/format/2409.11347">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> </div> <p class="title is-5 mathjax"> Hertzsprung gap stars in nearby galaxies and the Quest for Luminous Red Novae Progenitors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Tranin%2C+H">Hugo Tranin</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Karambelkar%2C+V">Viraj Karambelkar</a>, <a href="/search/astro-ph?searchtype=author&query=Groot%2C+P+J">Paul J. Groot</a>, <a href="/search/astro-ph?searchtype=author&query=Bloemen%2C+S">Steven Bloemen</a>, <a href="/search/astro-ph?searchtype=author&query=Vreeswijk%2C+P+M">Paul M. Vreeswijk</a>, <a href="/search/astro-ph?searchtype=author&query=Pieterse%2C+D+L+A">Dani毛lle L. A. Pieterse</a>, <a href="/search/astro-ph?searchtype=author&query=van+Roestel%2C+J">Jan van Roestel</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2409.11347v2-abstract-short" style="display: inline;"> After the main sequence phase, stars more massive than 2.5 M$_\odot$ rapidly evolve through the Hertzsprung gap as yellow giants and supergiants (YSG), before settling into the red giant branch. Identifying YSG in nearby galaxies is crucial for pinpointing progenitors of luminous red novae (LRNe) - astrophysical transients attributed to stellar mergers. In the era of extensive transient surveys li… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.11347v2-abstract-full').style.display = 'inline'; document.getElementById('2409.11347v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2409.11347v2-abstract-full" style="display: none;"> After the main sequence phase, stars more massive than 2.5 M$_\odot$ rapidly evolve through the Hertzsprung gap as yellow giants and supergiants (YSG), before settling into the red giant branch. Identifying YSG in nearby galaxies is crucial for pinpointing progenitors of luminous red novae (LRNe) - astrophysical transients attributed to stellar mergers. In the era of extensive transient surveys like the Vera Rubin Observatory's LSST, this approach offers a new way to predict and select common envelope transients. This study investigates potential progenitors and precursors of LRNe by analysing Hubble Space Telescope (HST) photometry of stellar populations in galaxies within 20 Mpc to identify YSG candidates. Additionally, we use ZTF and MeerLICHT/BlackGEM to identify possible precursors, preparing for future observations by the LSST. We compiled a sample of 369 galaxies with HST exposures in the F475W, F555W, F606W, and F814W filters. We identified YSG candidates using MESA stellar evolution tracks and statistical analysis of color-magnitude diagrams (CMDs). Our sample includes 154,494 YSG candidates with masses between 3 and 20 $M_\odot$ and is affected by various contaminants, such as foreground stars and extinguished main-sequence stars. After excluding foreground stars using Gaia proper motions, contamination is estimated at 1\% from foreground stars and 20\% from extinction affecting main-sequence stars. Combining our YSG candidates with time-domain catalogs yielded several interesting candidates. Notably, we identified 12 LRN precursor candidates for which followup is encouraged. We highlight the importance of monitoring future transients that match YSG candidates to avoid missing potential LRNe and other rare transients. LSST will be a game changer in the search for LRN progenitors and precursors, discovering over 300,000 new YSG and 100 precursors within 20 Mpc. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2409.11347v2-abstract-full').style.display = 'none'; document.getElementById('2409.11347v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 17 September, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Revised version submitted to A\&A. 17 pages, 21 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2405.18923">arXiv:2405.18923</a> <span> [<a href="https://arxiv.org/pdf/2405.18923">pdf</a>, <a href="https://arxiv.org/format/2405.18923">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/ad8b6a">10.1088/1538-3873/ad8b6a <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The BlackGEM telescope array I: Overview </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Groot%2C+P+J">Paul J. Groot</a>, <a href="/search/astro-ph?searchtype=author&query=Bloemen%2C+S">S. Bloemen</a>, <a href="/search/astro-ph?searchtype=author&query=Vreeswijk%2C+P">P. Vreeswijk</a>, <a href="/search/astro-ph?searchtype=author&query=van+Roestel%2C+J">J. van Roestel</a>, <a href="/search/astro-ph?searchtype=author&query=Jonker%2C+P+G">P. G. Jonker</a>, <a href="/search/astro-ph?searchtype=author&query=Nelemans%2C+G">G. Nelemans</a>, <a href="/search/astro-ph?searchtype=author&query=Klein-Wolt%2C+M">M. Klein-Wolt</a>, <a href="/search/astro-ph?searchtype=author&query=Poole%2C+R+L">R. Le Poole</a>, <a href="/search/astro-ph?searchtype=author&query=Pieterse%2C+D">D. Pieterse</a>, <a href="/search/astro-ph?searchtype=author&query=Rodenhuis%2C+M">M. Rodenhuis</a>, <a href="/search/astro-ph?searchtype=author&query=Boland%2C+W">W. Boland</a>, <a href="/search/astro-ph?searchtype=author&query=Haverkorn%2C+M">M. Haverkorn</a>, <a href="/search/astro-ph?searchtype=author&query=Aerts%2C+C">C. Aerts</a>, <a href="/search/astro-ph?searchtype=author&query=Bakker%2C+R">R. Bakker</a>, <a href="/search/astro-ph?searchtype=author&query=Balster%2C+H">H. Balster</a>, <a href="/search/astro-ph?searchtype=author&query=Bekema%2C+M">M. Bekema</a>, <a href="/search/astro-ph?searchtype=author&query=Dijkstra%2C+E">E. Dijkstra</a>, <a href="/search/astro-ph?searchtype=author&query=Dolron%2C+P">P. Dolron</a>, <a href="/search/astro-ph?searchtype=author&query=Elswijk%2C+E">E. Elswijk</a>, <a href="/search/astro-ph?searchtype=author&query=van+Elteren%2C+A">A. van Elteren</a>, <a href="/search/astro-ph?searchtype=author&query=Engels%2C+A">A. Engels</a>, <a href="/search/astro-ph?searchtype=author&query=Fokker%2C+M">M. Fokker</a>, <a href="/search/astro-ph?searchtype=author&query=de+Haan%2C+M">M. de Haan</a>, <a href="/search/astro-ph?searchtype=author&query=Hahn%2C+F">F. Hahn</a>, <a href="/search/astro-ph?searchtype=author&query=ter+Horst%2C+R">R. ter Horst</a> , et al. (53 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2405.18923v4-abstract-short" style="display: inline;"> The main science aim of the BlackGEM array is to detect optical counterparts to gravitational wave mergers. Additionally, the array will perform a set of synoptic surveys to detect Local Universe transients and short time-scale variability in stars and binaries, as well as a six-filter all-sky survey down to ~22nd mag. The BlackGEM Phase-I array consists of three optical wide-field unit telescopes… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.18923v4-abstract-full').style.display = 'inline'; document.getElementById('2405.18923v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2405.18923v4-abstract-full" style="display: none;"> The main science aim of the BlackGEM array is to detect optical counterparts to gravitational wave mergers. Additionally, the array will perform a set of synoptic surveys to detect Local Universe transients and short time-scale variability in stars and binaries, as well as a six-filter all-sky survey down to ~22nd mag. The BlackGEM Phase-I array consists of three optical wide-field unit telescopes. Each unit uses an f/5.5 modified Dall-Kirkham (Harmer-Wynne) design with a triplet corrector lens, and a 65cm primary mirror, coupled with a 110Mpix CCD detector, that provides an instantaneous field-of-view of 2.7~square degrees, sampled at 0.564\arcsec/pixel. The total field-of-view for the array is 8.2 square degrees. Each telescope is equipped with a six-slot filter wheel containing an optimised Sloan set (BG-u, BG-g, BG-r, BG-i, BG-z) and a wider-band 440-720 nm (BG-q) filter. Each unit telescope is independent from the others. Cloud-based data processing is done in real time, and includes a transient-detection routine as well as a full-source optimal-photometry module. BlackGEM has been installed at the ESO La Silla observatory as of October 2019. After a prolonged COVID-19 hiatus, science operations started on April 1, 2023 and will run for five years. Aside from its core scientific program, BlackGEM will give rise to a multitude of additional science cases in multi-colour time-domain astronomy, to the benefit of a variety of topics in astrophysics, such as infant supernovae, luminous red novae, asteroseismology of post-main-sequence objects, (ultracompact) binary stars, and the relation between gravitational wave counterparts and other classes of transients <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2405.18923v4-abstract-full').style.display = 'none'; document.getElementById('2405.18923v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 November, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 29 May, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2024. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Published in PASP</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> PASP 136 115003 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2304.10416">arXiv:2304.10416</a> <span> [<a href="https://arxiv.org/pdf/2304.10416">pdf</a>, <a href="https://arxiv.org/format/2304.10416">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> </div> <p class="title is-5 mathjax"> A Superluminous Supernova Lightened by Collisions with Pulsational Pair-instability Shells </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lin%2C+W">Weili Lin</a>, <a href="/search/astro-ph?searchtype=author&query=Wang%2C+X">Xiaofeng Wang</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Mo%2C+J">Jun Mo</a>, <a href="/search/astro-ph?searchtype=author&query=Brink%2C+T+G">Thomas G. Brink</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">Alexei V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Xiang%2C+D">Danfeng Xiang</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">Ragnhild Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Zheng%2C+W">Weikang Zheng</a>, <a href="/search/astro-ph?searchtype=author&query=Brown%2C+P">Peter Brown</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M">Mansi Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Mirzaqulov%2C+D">Davron Mirzaqulov</a>, <a href="/search/astro-ph?searchtype=author&query=Ehgamberdiev%2C+S+A">Shuhrat A. Ehgamberdiev</a>, <a href="/search/astro-ph?searchtype=author&query=Lin%2C+H">Han Lin</a>, <a href="/search/astro-ph?searchtype=author&query=Zhang%2C+K">Kaicheng Zhang</a>, <a href="/search/astro-ph?searchtype=author&query=Zhang%2C+J">Jicheng Zhang</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+S">Shengyu Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Zhang%2C+J">Jujia Zhang</a>, <a href="/search/astro-ph?searchtype=author&query=Chen%2C+Z">Zhihao Chen</a>, <a href="/search/astro-ph?searchtype=author&query=Deng%2C+L">Licai Deng</a>, <a href="/search/astro-ph?searchtype=author&query=Wang%2C+K">Kun Wang</a>, <a href="/search/astro-ph?searchtype=author&query=Xiao%2C+L">Lin Xiao</a> , et al. (1 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2304.10416v2-abstract-short" style="display: inline;"> Superluminous supernovae are among the most energetic stellar explosions in the Universe, but their energy sources remain an open question. Here we present long-term observations of one of the closest examples of the hydrogen-poor subclass (SLSNe-I), SN~2017egm, revealing the most complicated known luminosity evolution of SLSNe-I. Three distinct post-peak bumps were recorded in its light curve col… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.10416v2-abstract-full').style.display = 'inline'; document.getElementById('2304.10416v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2304.10416v2-abstract-full" style="display: none;"> Superluminous supernovae are among the most energetic stellar explosions in the Universe, but their energy sources remain an open question. Here we present long-term observations of one of the closest examples of the hydrogen-poor subclass (SLSNe-I), SN~2017egm, revealing the most complicated known luminosity evolution of SLSNe-I. Three distinct post-peak bumps were recorded in its light curve collected at about $100$--350\,days after maximum brightness, challenging current popular power models such as magnetar, fallback accretion, and interaction between ejecta and a circumstellar shell. However, the complex light curve can be well modelled by successive interactions with multiple circumstellar shells with a total mass of about $6.8$--7.7\,M$_\odot$. In this scenario, large energy deposition from interaction-induced reverse shocks results in ionization of neutral oxygen in the supernova ejecta and hence a much lower nebular-phase line ratio of [O\,\textsc{i}] $\lambda6300$/([Ca\,\textsc{ii}] + [O\,\textsc{ii}]) $\lambda7300$ ($\sim 0.2$) compared with that derived for other superluminous and normal stripped-envelope SNe. The pre-existing multiple shells indicate that the progenitor of SN~2017egm experienced pulsational mass ejections triggered by pair instability within 2 years before explosion, in robust agreement with theoretical predictions for a pre-pulsation helium-core mass of 48--51\,M$_{\odot}$. Finally, this work shows that the final explosion product may be a black hole with about 40\,M$_{\odot}$, and has significant implication for the formation of such heavy black holes that have been recently observed by LIGO-Virgo gravitational wave detectors. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2304.10416v2-abstract-full').style.display = 'none'; document.getElementById('2304.10416v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 20 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 20 April, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">34 pages, 13 figures, 6 tables</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2212.03313">arXiv:2212.03313</a> <span> [<a href="https://arxiv.org/pdf/2212.03313">pdf</a>, <a href="https://arxiv.org/format/2212.03313">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/acd8be">10.3847/1538-4357/acd8be <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The prevalence and influence of circumstellar material around hydrogen-rich supernova progenitors </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bruch%2C+R+J">Rachel J. Bruch</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Yaron%2C+O">Ofer Yaron</a>, <a href="/search/astro-ph?searchtype=author&query=Chen%2C+P">Ping Chen</a>, <a href="/search/astro-ph?searchtype=author&query=Strotjohann%2C+N+L">Nora L. Strotjohann</a>, <a href="/search/astro-ph?searchtype=author&query=Irani%2C+I">Ido Irani</a>, <a href="/search/astro-ph?searchtype=author&query=Zimmerman%2C+E">Erez Zimmerman</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">Steve Schulze</a>, <a href="/search/astro-ph?searchtype=author&query=Yang%2C+Y">Yi Yang</a>, <a href="/search/astro-ph?searchtype=author&query=Kim%2C+Y">Young-Lo Kim</a>, <a href="/search/astro-ph?searchtype=author&query=Bulla%2C+M">Mattia Bulla</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Rigault%2C+M">Mickael Rigault</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E">Eran Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Soumagnac%2C+M">Maayane Soumagnac</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D">Daniel Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">Jakob Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S">S. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Adreoni%2C+I">Igor Adreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a> , et al. (22 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2212.03313v2-abstract-short" style="display: inline;"> Narrow transient emission lines (flash-ionization features) in early supernova (SN) spectra trace the presence of circumstellar material (CSM) around the massive progenitor stars of core-collapse SNe. The lines disappear within days after the SN explosion, suggesting that this material is spatially confined, and originates from enhanced mass loss shortly (months to a few years) prior to explosion.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.03313v2-abstract-full').style.display = 'inline'; document.getElementById('2212.03313v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2212.03313v2-abstract-full" style="display: none;"> Narrow transient emission lines (flash-ionization features) in early supernova (SN) spectra trace the presence of circumstellar material (CSM) around the massive progenitor stars of core-collapse SNe. The lines disappear within days after the SN explosion, suggesting that this material is spatially confined, and originates from enhanced mass loss shortly (months to a few years) prior to explosion. We performed a systematic survey of H-rich (Type II) SNe discovered within less than two days from explosion during the first phase of the Zwicky Transient Facility (ZTF) survey (2018-2020), finding thirty events for which a first spectrum was obtained within $< 2$ days from explosion. The measured fraction of events showing flash ionisation features ($>36\%$ at $95\%$ confidence level) confirms that elevated mass loss in massive stars prior to SN explosion is common. We find that SNe II showing flash ionisation features are not significantly brighter, nor bluer, nor more slowly rising than those without. This implies that CSM interaction does not contribute significantly to their early continuum emission, and that the CSM is likely optically thin. We measured the persistence duration of flash ionisation emission and find that most SNe show flash features for $\approx 5 $ days. Rarer events, with persistence timescales $>10$ days, are brighter and rise longer, suggesting these may be intermediate between regular SNe II and strongly-interacting SNe IIn. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2212.03313v2-abstract-full').style.display = 'none'; document.getElementById('2212.03313v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 13 December, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 6 December, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2022. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2211.05141">arXiv:2211.05141</a> <span> [<a href="https://arxiv.org/pdf/2211.05141">pdf</a>, <a href="https://arxiv.org/format/2211.05141">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/acc2b9">10.3847/1538-4357/acc2b9 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Volumetric rates of Luminous Red Novae and Intermediate Luminosity Red Transients with the Zwicky Transient Facility </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Karambelkar%2C+V+R">Viraj R. Karambelkar</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Aloisi%2C+R">Robert Aloisi</a>, <a href="/search/astro-ph?searchtype=author&query=Anand%2C+S+G">Shreya G. Anand</a>, <a href="/search/astro-ph?searchtype=author&query=Andreoni%2C+I">Igor Andreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Brink%2C+T+G">Thomas G. Brink</a>, <a href="/search/astro-ph?searchtype=author&query=Bruch%2C+R">Rachel Bruch</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D">David Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Das%2C+K+K">Kaustav Kashyap Das</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Drake%2C+A">Andrew Drake</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">Alexei V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Helou%2C+G">George Helou</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A">Anna Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J">Jacob Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Jones%2C+D">David Jones</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Patra%2C+K+C">Kishore C. Patra</a>, <a href="/search/astro-ph?searchtype=author&query=Purdum%2C+J">Josiah Purdum</a>, <a href="/search/astro-ph?searchtype=author&query=Reedy%2C+A">Alexander Reedy</a>, <a href="/search/astro-ph?searchtype=author&query=Sit%2C+T">Tawny Sit</a> , et al. (5 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2211.05141v1-abstract-short" style="display: inline;"> Luminous red novae (LRNe) are transients characterized by low luminosities and expansion velocities, and are associated with mergers or common envelope ejections in stellar binaries. Intermediate-luminosity red transients (ILRTs) are an observationally similar class with unknown origins, but generally believed to either be electron capture supernovae (ECSN) in super-AGB stars, or outbursts in dust… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.05141v1-abstract-full').style.display = 'inline'; document.getElementById('2211.05141v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2211.05141v1-abstract-full" style="display: none;"> Luminous red novae (LRNe) are transients characterized by low luminosities and expansion velocities, and are associated with mergers or common envelope ejections in stellar binaries. Intermediate-luminosity red transients (ILRTs) are an observationally similar class with unknown origins, but generally believed to either be electron capture supernovae (ECSN) in super-AGB stars, or outbursts in dusty luminous blue variables (LBVs). In this paper, we present a systematic sample of 8 LRNe and 8 ILRTs detected as part of the Census of the Local Universe (CLU) experiment on the Zwicky Transient Facility (ZTF). The CLU experiment spectroscopically classifies ZTF transients associated with nearby ($<150$ Mpc) galaxies, achieving 80% completeness for m$_{r}<20$\,mag. Using the ZTF-CLU sample, we derive the first systematic LRNe volumetric-rate of 7.8$^{+6.5}_{-3.7}\times10^{-5}$ Mpc$^{-3}$ yr$^{-1}$ in the luminosity range $-16\leq$M$_{\rm{r}}$$\leq -11$ mag. We find that in this luminosity range, the LRN rate scales as dN/dL $\propto L^{-2.5\pm0.3}$ - significantly steeper than the previously derived scaling of $L^{-1.4\pm0.3}$ for lower luminosity LRNe (M$_{V}\geq-10$). The steeper power law for LRNe at high luminosities is consistent with the massive merger rates predicted by binary population synthesis models. We find that the rates of the brightest LRNe (M$_{r}\leq-13$ mag) are consistent with a significant fraction of them being progenitors of double compact objects (DCOs) that merge within a Hubble time. For ILRTs, we derive a volumetric rate of $2.6^{+1.8}_{-1.4}\times10^{-6}$ Mpc$^{-3}$yr$^{-1}$ for M$_{\rm{r}}\leq-13.5$, that scales as dN/dL $\propto L^{-2.5\pm0.5}$. This rate is $\approx1-5\%$ of the local core-collapse supernova rate, and is consistent with theoretical ECSN rate estimates. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.05141v1-abstract-full').style.display = 'none'; document.getElementById('2211.05141v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 November, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">32 pages, 16 figures. Submitted to ApJ, comments welcome</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2206.07070">arXiv:2206.07070</a> <span> [<a href="https://arxiv.org/pdf/2206.07070">pdf</a>, <a href="https://arxiv.org/format/2206.07070">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/stac2685">10.1093/mnras/stac2685 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Searching for the Next Galactic Luminous Red Nova </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Addison%2C+H">Harry Addison</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Groot%2C+P+J">Paul J. Groot</a>, <a href="/search/astro-ph?searchtype=author&query=Erasmus%2C+N">Nicolas Erasmus</a>, <a href="/search/astro-ph?searchtype=author&query=Jones%2C+D">David Jones</a>, <a href="/search/astro-ph?searchtype=author&query=Mogawana%2C+O">Orapeleng Mogawana</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2206.07070v2-abstract-short" style="display: inline;"> Luminous red novae (LRNe) are astrophysical transients believed to be caused by the partial ejection of a binary star's common envelope (CE) and the merger of its components. The formation of the CE is likely to occur during unstable mass transfer, initiated by a primary star which is evolving off the main sequence (a Hertzsprung gap star) and a lower mass companion. In agreement with observations… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2206.07070v2-abstract-full').style.display = 'inline'; document.getElementById('2206.07070v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2206.07070v2-abstract-full" style="display: none;"> Luminous red novae (LRNe) are astrophysical transients believed to be caused by the partial ejection of a binary star's common envelope (CE) and the merger of its components. The formation of the CE is likely to occur during unstable mass transfer, initiated by a primary star which is evolving off the main sequence (a Hertzsprung gap star) and a lower mass companion. In agreement with observations, theoretical studies have shown that outflows from the pre-CE phase produce a detectable brightening of the progenitor system a few years before the ejection event. Based on these assumptions, we present a method to identify Galactic LRNe precursors, the resulting precursor candidates, and our follow-up analysis to uncover their nature. We begin by constructing a sample of progenitor systems, i.e. Hertzsprung gap stars, by statistically modelling the density of a colour magnitude diagram formed from "well behaved" Gaia DR2 sources. Their time-domain evolution from the Zwicky Transient Facility (ZTF) survey is used to search for slowly brightening events, as pre-CE precursor candidates. The nature of the resulting candidates is further investigated using archival data and our own spectroscopic follow-up. Overall, we constructed a sample of $\sim5.4\times{10^4}$ progenitor sources, from which 21 were identified as candidate LRNe precursors. Further analysis revealed 16 of our candidates to be H$伪$ emitters, with their spectra often suggesting hotter (albeit moderately extincted) A-type or B-type stars. Because of their long-term variability in optical and mid-infrared wavelengths, we propose that many of our candidates are mass-transferring binaries with compact companions surrounded by dusty circumstellar disks or alternatively magnetically active stellar merger remnants. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2206.07070v2-abstract-full').style.display = 'none'; document.getElementById('2206.07070v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 September, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 14 June, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2022. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in MNRAS (23rd September 2022)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2106.01394">arXiv:2106.01394</a> <span> [<a href="https://arxiv.org/pdf/2106.01394">pdf</a>, <a href="https://arxiv.org/format/2106.01394">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/202140735">10.1051/0004-6361/202140735 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gaia Photometric Science Alerts </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Hodgkin%2C+S+T">S. T. Hodgkin</a>, <a href="/search/astro-ph?searchtype=author&query=Harrison%2C+D+L">D. L. Harrison</a>, <a href="/search/astro-ph?searchtype=author&query=Breedt%2C+E">E. Breedt</a>, <a href="/search/astro-ph?searchtype=author&query=Wevers%2C+T">T. Wevers</a>, <a href="/search/astro-ph?searchtype=author&query=Rixon%2C+G">G. Rixon</a>, <a href="/search/astro-ph?searchtype=author&query=Delgado%2C+A">A. Delgado</a>, <a href="/search/astro-ph?searchtype=author&query=Yoldas%2C+A">A. Yoldas</a>, <a href="/search/astro-ph?searchtype=author&query=Kostrzewa-Rutkowska%2C+Z">Z. Kostrzewa-Rutkowska</a>, <a href="/search/astro-ph?searchtype=author&query=Wyrzykowski%2C+%C5%81">艁. Wyrzykowski</a>, <a href="/search/astro-ph?searchtype=author&query=van+Leeuwen%2C+M">M. van Leeuwen</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Campbell%2C+H">H. Campbell</a>, <a href="/search/astro-ph?searchtype=author&query=Eappachen%2C+D">D. Eappachen</a>, <a href="/search/astro-ph?searchtype=author&query=Fraser%2C+M">M. Fraser</a>, <a href="/search/astro-ph?searchtype=author&query=Ihanec%2C+N">N. Ihanec</a>, <a href="/search/astro-ph?searchtype=author&query=Koposov%2C+S+E">S. E. Koposov</a>, <a href="/search/astro-ph?searchtype=author&query=Kruszy%C5%84ska%2C+K">K. Kruszy艅ska</a>, <a href="/search/astro-ph?searchtype=author&query=Marton%2C+G">G. Marton</a>, <a href="/search/astro-ph?searchtype=author&query=Rybicki%2C+K+A">K. A. Rybicki</a>, <a href="/search/astro-ph?searchtype=author&query=Brown%2C+A+G+A">A. G. A. Brown</a>, <a href="/search/astro-ph?searchtype=author&query=Burgess%2C+P+W">P. W. Burgess</a>, <a href="/search/astro-ph?searchtype=author&query=Busso%2C+G">G. Busso</a>, <a href="/search/astro-ph?searchtype=author&query=Cowell%2C+S">S. Cowell</a>, <a href="/search/astro-ph?searchtype=author&query=De+Angeli%2C+F">F. De Angeli</a>, <a href="/search/astro-ph?searchtype=author&query=Diener%2C+C">C. Diener</a> , et al. (86 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2106.01394v1-abstract-short" style="display: inline;"> Since July 2014, the Gaia mission has been engaged in a high-spatial-resolution, time-resolved, precise, accurate astrometric, and photometric survey of the entire sky. Aims: We present the Gaia Science Alerts project, which has been in operation since 1 June 2016. We describe the system which has been developed to enable the discovery and publication of transient photometric events as seen by G… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.01394v1-abstract-full').style.display = 'inline'; document.getElementById('2106.01394v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2106.01394v1-abstract-full" style="display: none;"> Since July 2014, the Gaia mission has been engaged in a high-spatial-resolution, time-resolved, precise, accurate astrometric, and photometric survey of the entire sky. Aims: We present the Gaia Science Alerts project, which has been in operation since 1 June 2016. We describe the system which has been developed to enable the discovery and publication of transient photometric events as seen by Gaia. Methods: We outline the data handling, timings, and performances, and we describe the transient detection algorithms and filtering procedures needed to manage the high false alarm rate. We identify two classes of events: (1) sources which are new to Gaia and (2) Gaia sources which have undergone a significant brightening or fading. Validation of the Gaia transit astrometry and photometry was performed, followed by testing of the source environment to minimise contamination from Solar System objects, bright stars, and fainter near-neighbours. Results: We show that the Gaia Science Alerts project suffers from very low contamination, that is there are very few false-positives. We find that the external completeness for supernovae, $C_E=0.46$, is dominated by the Gaia scanning law and the requirement of detections from both fields-of-view. Where we have two or more scans the internal completeness is $C_I=0.79$ at 3 arcsec or larger from the centres of galaxies, but it drops closer in, especially within 1 arcsec. Conclusions: The per-transit photometry for Gaia transients is precise to 1 per cent at $G=13$, and 3 per cent at $G=19$. The per-transit astrometry is accurate to 55 milliarcseconds when compared to Gaia DR2. The Gaia Science Alerts project is one of the most homogeneous and productive transient surveys in operation, and it is the only survey which covers the whole sky at high spatial resolution (subarcsecond), including the Galactic plane and bulge. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.01394v1-abstract-full').style.display = 'none'; document.getElementById('2106.01394v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 2 June, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">26 pages, 26 figures, accepted for publication in Astronomy & Astrophysics</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 652, A76 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2102.11291">arXiv:2102.11291</a> <span> [<a href="https://arxiv.org/pdf/2102.11291">pdf</a>, <a href="https://arxiv.org/format/2102.11291">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ac1424">10.3847/1538-4357/ac1424 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> AT 2019qyl in NGC 300: Internal Collisions in the Early Outflow from a Very Fast Nova in a Symbiotic Binary </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Andrews%2C+J+E">Jennifer E. Andrews</a>, <a href="/search/astro-ph?searchtype=author&query=Bond%2C+H+E">Howard E. Bond</a>, <a href="/search/astro-ph?searchtype=author&query=Karambelkar%2C+V">Viraj Karambelkar</a>, <a href="/search/astro-ph?searchtype=author&query=Sand%2C+D+J">David J. Sand</a>, <a href="/search/astro-ph?searchtype=author&query=van+Dyk%2C+S+D">Schuyler D. van Dyk</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Boyer%2C+M+L">Martha L. Boyer</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R+M">Ryan M. Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Mohamed%2C+S">Shazrene Mohamed</a>, <a href="/search/astro-ph?searchtype=author&query=Williams%2C+R">Robert Williams</a>, <a href="/search/astro-ph?searchtype=author&query=Whitelock%2C+P+A">Patricia A. Whitelock</a>, <a href="/search/astro-ph?searchtype=author&query=Amaro%2C+R+C">Rachael C. Amaro</a>, <a href="/search/astro-ph?searchtype=author&query=Bostroem%2C+K+A">K. Azalee Bostroem</a>, <a href="/search/astro-ph?searchtype=author&query=Dong%2C+Y">Yize Dong</a>, <a href="/search/astro-ph?searchtype=author&query=Lundquist%2C+M+J">Michael J. Lundquist</a>, <a href="/search/astro-ph?searchtype=author&query=Valenti%2C+S">Stefano Valenti</a>, <a href="/search/astro-ph?searchtype=author&query=Wyatt%2C+S+D">Samuel D. Wyatt</a>, <a href="/search/astro-ph?searchtype=author&query=Burke%2C+J">Jamie Burke</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Jha%2C+S+W">Saurabh W. Jha</a>, <a href="/search/astro-ph?searchtype=author&query=Johansson%2C+J">Joel Johansson</a>, <a href="/search/astro-ph?searchtype=author&query=Rojas-Bravo%2C+C">C茅sar Rojas-Bravo</a>, <a href="/search/astro-ph?searchtype=author&query=Coulter%2C+D+A">David A. Coulter</a> , et al. (17 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2102.11291v2-abstract-short" style="display: inline;"> Nova eruptions, thermonuclear explosions on the surfaces of white dwarfs (WDs), are now recognized to be among the most common shock-powered astrophysical transients. We present the early discovery and rapid ultraviolet (UV), optical, and infrared (IR) temporal development of AT 2019qyl, a recent nova in the nearby Sculptor Group galaxy NGC 300. The light curve shows a rapid rise lasting… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.11291v2-abstract-full').style.display = 'inline'; document.getElementById('2102.11291v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2102.11291v2-abstract-full" style="display: none;"> Nova eruptions, thermonuclear explosions on the surfaces of white dwarfs (WDs), are now recognized to be among the most common shock-powered astrophysical transients. We present the early discovery and rapid ultraviolet (UV), optical, and infrared (IR) temporal development of AT 2019qyl, a recent nova in the nearby Sculptor Group galaxy NGC 300. The light curve shows a rapid rise lasting $\lesssim 1$ day, reaching a peak absolute magnitude of $M_V = -9.2$ mag, and a very fast decline, fading by 2 mag over 3.5 days. A steep dropoff in the light curves after 71 days and the rapid decline timescale suggest a low-mass ejection from a massive WD with $M_{\rm WD} \gtrsim 1.2~M_{\odot}$. We present an unprecedented view of the early spectroscopic evolution of such an event. Three spectra prior to the peak reveal a complex, multicomponent outflow giving rise to internal collisions and shocks in the ejecta of an He/N-class nova. We identify a coincident IR-variable counterpart in the extensive preeruption coverage of the transient location and infer the presence of a symbiotic progenitor system with an O-rich asymptotic-giant-branch donor star, as well as evidence for an earlier UV-bright outburst in 2014. We suggest that AT 2019qyl is analogous to the subset of Galactic recurrent novae with red-giant companions such as RS Oph and other embedded nova systems like V407 Cyg. Our observations provide new evidence that internal shocks between multiple, distinct outflow components likely contribute to the generation of the shock-powered emission from such systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.11291v2-abstract-full').style.display = 'none'; document.getElementById('2102.11291v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 September, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 February, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">32 pages, 10 figures, accepted in ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2102.05662">arXiv:2102.05662</a> <span> [<a href="https://arxiv.org/pdf/2102.05662">pdf</a>, <a href="https://arxiv.org/format/2102.05662">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/202140525">10.1051/0004-6361/202140525 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The luminous red nova AT 2018bwo in NGC 45 and its binary yellow supergiant progenitor </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Klencki%2C+J">Jakub Klencki</a>, <a href="/search/astro-ph?searchtype=author&query=Pejcha%2C+O">Ondrej Pejcha</a>, <a href="/search/astro-ph?searchtype=author&query=Vreeswijk%2C+P+M">Paul M. Vreeswijk</a>, <a href="/search/astro-ph?searchtype=author&query=Bond%2C+H+E">Howard E. Bond</a>, <a href="/search/astro-ph?searchtype=author&query=Burdge%2C+K+B">Kevin B. Burdge</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gehrz%2C+R+D">Robert D. Gehrz</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">Thomas Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R+M">Ryan M. Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Rich%2C+R+M">R. Michael Rich</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2102.05662v2-abstract-short" style="display: inline;"> Luminous Red Novae (LRNe) are astrophysical transients associated with the partial ejection of a binary system's common envelope (CE) shortly before its merger. Here we present the results of our photometric and spectroscopic follow-up campaign of AT2018bwo (DLT18x), a LRN discovered in NGC45, and investigate its progenitor system using binary stellar-evolution models. The transient reached a peak… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.05662v2-abstract-full').style.display = 'inline'; document.getElementById('2102.05662v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2102.05662v2-abstract-full" style="display: none;"> Luminous Red Novae (LRNe) are astrophysical transients associated with the partial ejection of a binary system's common envelope (CE) shortly before its merger. Here we present the results of our photometric and spectroscopic follow-up campaign of AT2018bwo (DLT18x), a LRN discovered in NGC45, and investigate its progenitor system using binary stellar-evolution models. The transient reached a peak magnitude of $M_r=-10.97\pm0.11$ and maintained this brightness during its optical plateau of $t_p = 41\pm5$days. During this phase, it showed a rather stable photospheric temperature of ~3300K and a luminosity of ~$10^{40}$erg/s. The photosphere of AT2018bwo at early times appeared larger and cooler than other similar LRNe, likely due to an extended mass-loss episode before the merger. Towards the end of the plateau, optical spectra showed a reddened continuum with strong molecular absorption bands. The reprocessed emission by the cooling dust was also detected in the mid-infrared bands ~1.5 years after the outburst. Archival Spitzer and Hubble Space Telescope data taken 10-14 years before the transient event suggest a progenitor star with $T_{prog}\sim 6500$K, $R_{prog}\sim 100R_{\odot}$ and $L_{prog}\sim 2\times10^4L_{\odot}$, and an upper limit for optically thin warm (1000 K) dust mass of $M_d<10^{-6}M_{\odot}$. Using stellar binary-evolution models, we determined the properties of binary systems consistent with the progenitor parameter space. For AT2018bwo, we infer a primary mass of 12-16 $M_{\odot}$, which is 9-45% larger than the ~11$M_{\odot}$ obtained using single-star evolution models. The system, consistent with a yellow-supergiant primary, was likely in a stable mass-transfer regime with -2.4<log ($\dot{M}/M_{\odot}$/yr)<-1.2 a decade before the main instability occurred. During the dynamical merger, the system would have ejected 0.15-0.5$M_{\odot}$ with a velocity of ~500 km/s. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.05662v2-abstract-full').style.display = 'none'; document.getElementById('2102.05662v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 January, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 10 February, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2021. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 16 figures, accepted version for A&A</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 653, A134 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2008.09986">arXiv:2008.09986</a> <span> [<a href="https://arxiv.org/pdf/2008.09986">pdf</a>, <a href="https://arxiv.org/format/2008.09986">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/abef05">10.3847/1538-4357/abef05 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A large fraction of hydrogen-rich supernova progenitors experience elevated mass loss shortly prior to explosion </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bruch%2C+R+J">Rachel J. Bruch</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">Steve Schulze</a>, <a href="/search/astro-ph?searchtype=author&query=Yaron%2C+O">Ofer Yaron</a>, <a href="/search/astro-ph?searchtype=author&query=Yang%2C+Y">Yi Yang</a>, <a href="/search/astro-ph?searchtype=author&query=Soumagnac%2C+M+T">Maayane T. Soumagnac</a>, <a href="/search/astro-ph?searchtype=author&query=Rigault%2C+M">Mickael Rigault</a>, <a href="/search/astro-ph?searchtype=author&query=Strotjohann%2C+N+L">Nora L. Strotjohann</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E">Eran Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">Cristina Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D">Daniel Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">Jakob Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S">S. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Adreoni%2C+I">Igor Adreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bulla%2C+M">Mattia Bulla</a>, <a href="/search/astro-ph?searchtype=author&query=Burdge%2C+K">Kevin Burdge</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Dhawan%2C+S">Suhail Dhawan</a> , et al. (21 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2008.09986v1-abstract-short" style="display: inline;"> Spectroscopic detection of narrow emission lines traces the presence of circumstellar mass distributions around massive stars exploding as core-collapse supernovae. Transient emission lines disappearing shortly after the supernova explosion suggest that the spatial extent of such material is compact, and hence imply an increased mass loss shortly prior to explosion. Here, we present a systematic s… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.09986v1-abstract-full').style.display = 'inline'; document.getElementById('2008.09986v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2008.09986v1-abstract-full" style="display: none;"> Spectroscopic detection of narrow emission lines traces the presence of circumstellar mass distributions around massive stars exploding as core-collapse supernovae. Transient emission lines disappearing shortly after the supernova explosion suggest that the spatial extent of such material is compact, and hence imply an increased mass loss shortly prior to explosion. Here, we present a systematic survey for such transient emission lines (Flash Spectroscopy) among Type II supernovae detected in the first year of the Zwicky Transient Facility (ZTF) survey. We find that at least six out of ten events for which a spectrum was obtained within two days of estimated explosion time show evidence for such transient flash lines. Our measured flash event fraction ($>30\%$ at $95\%$ confidence level) indicates that elevated mass loss is a common process occurring in massive stars that are about to explode as supernovae. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.09986v1-abstract-full').style.display = 'none'; document.getElementById('2008.09986v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 August, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2020. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2007.13144">arXiv:2007.13144</a> <span> [<a href="https://arxiv.org/pdf/2007.13144">pdf</a>, <a href="https://arxiv.org/format/2007.13144">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/staa2191">10.1093/mnras/staa2191 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> PTF11rka: an interacting supernova at the crossroads of stripped-envelope and H-poor super-luminous stellar core collapses </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Pian%2C+E">Elena Pian</a>, <a href="/search/astro-ph?searchtype=author&query=Mazzali%2C+P+A">Paolo A. Mazzali</a>, <a href="/search/astro-ph?searchtype=author&query=Moriya%2C+T+J">Takashi J. Moriya</a>, <a href="/search/astro-ph?searchtype=author&query=Rubin%2C+A">Adam Rubin</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">Iair Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=Ben-Ami%2C+S">Sagi Ben-Ami</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bufano%2C+M">Milena Bufano</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">Alex V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M">Mansi Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">Shri R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">Ragnhild Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Manulis%2C+I">Ilan Manulis</a>, <a href="/search/astro-ph?searchtype=author&query=Matheson%2C+T">Tom Matheson</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">Peter E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E">Eran Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Dan A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Prentice%2C+S+J">Simon J. Prentice</a>, <a href="/search/astro-ph?searchtype=author&query=Yaron%2C+O">Ofer Yaron</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2007.13144v1-abstract-short" style="display: inline;"> The hydrogen-poor supernova PTF11rka (z = 0.0744), reported by the Palomar Transient Factory, was observed with various telescopes starting a few days after the estimated explosion time of 2011 Dec. 5 UT and up to 432 rest-frame days thereafter. The rising part of the light curve was monitored only in the R_PTF filter band, and maximum in this band was reached ~30 rest-frame days after the estimat… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.13144v1-abstract-full').style.display = 'inline'; document.getElementById('2007.13144v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2007.13144v1-abstract-full" style="display: none;"> The hydrogen-poor supernova PTF11rka (z = 0.0744), reported by the Palomar Transient Factory, was observed with various telescopes starting a few days after the estimated explosion time of 2011 Dec. 5 UT and up to 432 rest-frame days thereafter. The rising part of the light curve was monitored only in the R_PTF filter band, and maximum in this band was reached ~30 rest-frame days after the estimated explosion time. The light curve and spectra of PTF11rka are consistent with the core-collapse explosion of a ~10 Msun carbon-oxygen core evolved from a progenitor of main-sequence mass 25--40 Msun, that liberated a kinetic energy (KE) ~ 4 x 10^{51} erg, expelled ~8 Msun of ejecta (Mej), and synthesised ~0.5 Msun of 56Nichel. The photospheric spectra of PTF11rka are characterised by narrow absorption lines that point to suppression of the highest ejecta velocities ~>15,000 km/s. This would be expected if the ejecta impacted a dense, clumpy circumstellar medium. This in turn caused them to lose a fraction of their energy (~5 x 10^50 erg), less than 2% of which was converted into radiation that sustained the light curve before maximum brightness. This is reminiscent of the superluminous SN 2007bi, the light-curve shape and spectra of which are very similar to those of PTF11rka, although the latter is a factor of 10 less luminous and evolves faster in time. PTF11rka is in fact more similar to gamma-ray burst supernovae (GRB-SNe) in luminosity, although it has a lower energy and a lower KE/Mej ratio. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.13144v1-abstract-full').style.display = 'none'; document.getElementById('2007.13144v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 July, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">18 page, 9 figures, MNRAS, in press</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2006.14336">arXiv:2006.14336</a> <span> [<a href="https://arxiv.org/pdf/2006.14336">pdf</a>, <a href="https://arxiv.org/format/2006.14336">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aba3cc">10.3847/1538-4357/aba3cc <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Multi-wavelength Photometry and Progenitor Analysis of the Nova V906 Car </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Wee%2C+J">Jerrick Wee</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Penprase%2C+B+E">Bryan Edward Penprase</a>, <a href="/search/astro-ph?searchtype=author&query=Facey%2C+J+P">Jett Pierce Facey</a>, <a href="/search/astro-ph?searchtype=author&query=Morioka%2C+T">Taiga Morioka</a>, <a href="/search/astro-ph?searchtype=author&query=Corbett%2C+H">Hank Corbett</a>, <a href="/search/astro-ph?searchtype=author&query=Barlow%2C+B+N">Brad N. Barlow</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">Thomas Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Law%2C+N+M">Nicholas M. Law</a>, <a href="/search/astro-ph?searchtype=author&query=Ratzloff%2C+J+K">Jeffrey K. Ratzloff</a>, <a href="/search/astro-ph?searchtype=author&query=Howard%2C+W+S">Ward S. Howard</a>, <a href="/search/astro-ph?searchtype=author&query=Chavez%2C+R+G">Ramses Gonzalez Chavez</a>, <a href="/search/astro-ph?searchtype=author&query=Glazier%2C+A">Amy Glazier</a>, <a href="/search/astro-ph?searchtype=author&query=Soto%2C+A+V">Alan Vasquez Soto</a>, <a href="/search/astro-ph?searchtype=author&query=Horiuchi%2C+T">Takashi Horiuchi</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2006.14336v1-abstract-short" style="display: inline;"> We present optical and infrared photometry of the classical nova V906 Car, also known as Nova Car 2018 and ASASSN-18fv, discovered by ASASS-SN survey on 16.32 March 2018 UT (MJD 58193.0). The nova reached its maximum on MJD 58222.56 at $V_{\rm{max}} = 5.84 \pm 0.09$ mag and had decline times of $t_{2,V} = 26.2 $ d and $t_{3,V} = 33.0 $ d. The data from Evryscope shows that the nova had already bri… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.14336v1-abstract-full').style.display = 'inline'; document.getElementById('2006.14336v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2006.14336v1-abstract-full" style="display: none;"> We present optical and infrared photometry of the classical nova V906 Car, also known as Nova Car 2018 and ASASSN-18fv, discovered by ASASS-SN survey on 16.32 March 2018 UT (MJD 58193.0). The nova reached its maximum on MJD 58222.56 at $V_{\rm{max}} = 5.84 \pm 0.09$ mag and had decline times of $t_{2,V} = 26.2 $ d and $t_{3,V} = 33.0 $ d. The data from Evryscope shows that the nova had already brightened to $g'\simeq 13$\,mag five days before discovery, as compared to its quiescent magnitude of $g=$20.13$\pm$0.03. The extinction towards the nova, as derived from high resolution spectroscopy, shows an estimate consistent with foreground extinction to the Carina Nebula of $A_V = 1.11_{-0.39}^{+0.54}$. The light curve resembles a rare C (cusp) class nova with a steep decline slope of $伪=-3.94$ post cusp flare. From the lightcurve decline rate, we estimate the mass of white dwarf to be $M_{WD}$ = $ < 0.8$M\textsubscript{$\odot$}, consistent with $M_{WD}=0.71^{+0.23}_{-0.19}$ derived from modelling the accretion disk of the system in quiescence. The donor star is likely a K-M dwarf of 0.23-0.43\,\Msun, which is being heated by its companion. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2006.14336v1-abstract-full').style.display = 'none'; document.getElementById('2006.14336v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">13 pages, 10 figures, 7 tables. Accepted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2004.04757">arXiv:2004.04757</a> <span> [<a href="https://arxiv.org/pdf/2004.04757">pdf</a>, <a href="https://arxiv.org/format/2004.04757">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/staa1872">10.1093/mnras/staa1872 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Progenitor, Precursor and Evolution of the Dusty Remnant of the Stellar Merger M31-LRN-2015 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Karambelkar%2C+V">Viraj Karambelkar</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kochanek%2C+C+S">Christopher S. Kochanek</a>, <a href="/search/astro-ph?searchtype=author&query=Dong%2C+S">Subo Dong</a>, <a href="/search/astro-ph?searchtype=author&query=Campbell%2C+H">Heather Campbell</a>, <a href="/search/astro-ph?searchtype=author&query=Hodgkin%2C+S">Simon Hodgkin</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Johansson%2C+J">Joel Johansson</a>, <a href="/search/astro-ph?searchtype=author&query=Kozlowski%2C+S">Szymon Kozlowski</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F">Frank Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P">Peter Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Rebbapragada%2C+U+D">Umaa D. Rebbapragada</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.04757v2-abstract-short" style="display: inline;"> M31-2015-LRN is a likely stellar merger discovered in the Andromeda Galaxy in 2015. We present new optical to mid-infrared photometry and optical spectroscopy for this event. Archival data shows that the source started to brighten $\sim$2 years before the nova event. During this precursor phase, the source brightened by $\sim$3 mag. The lightcurve at 6 and 1.5 months before the main outburst may s… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.04757v2-abstract-full').style.display = 'inline'; document.getElementById('2004.04757v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.04757v2-abstract-full" style="display: none;"> M31-2015-LRN is a likely stellar merger discovered in the Andromeda Galaxy in 2015. We present new optical to mid-infrared photometry and optical spectroscopy for this event. Archival data shows that the source started to brighten $\sim$2 years before the nova event. During this precursor phase, the source brightened by $\sim$3 mag. The lightcurve at 6 and 1.5 months before the main outburst may show periodicity, with periods of 16$\pm$0.3 and 28.1$\pm$1.4 days respectively. This complex emission may be explained by runaway mass loss from the system after the binary undergoes Roche-lobe overflow, leading the system to coalesce in tens of orbital periods. While the progenitor spectral energy distribution shows no evidence of pre-existing warm dust in system, the remnant forms an optically thick dust shell at $\sim$4 months after the outburst peak. The optical depth of the shell increases dramatically after 1.5 years, suggesting the existence of shocks that enhance the dust formation process. We propose that the merger remnant is likely an inflated giant obscured by a cooling shell of gas with mass $\sim0.2$ M$_{\odot}$ ejected at the onset of the common envelope phase. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.04757v2-abstract-full').style.display = 'none'; document.getElementById('2004.04757v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 9 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">16 pages, 10 figures. Accepted for publication in MNRAS</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1910.14004">arXiv:1910.14004</a> <span> [<a href="https://arxiv.org/pdf/1910.14004">pdf</a>, <a href="https://arxiv.org/format/1910.14004">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Earth and Planetary Astrophysics">astro-ph.EP</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-3881/ab9305">10.3847/1538-3881/ab9305 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Characterization of the Nucleus, Morphology and Activity of Interstellar Comet 2I/Borisov by Optical and Near-Infrared GROWTH, Apache Point, IRTF, ZTF and Keck Observations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bolin%2C+B+T">Bryce T. Bolin</a>, <a href="/search/astro-ph?searchtype=author&query=Lisse%2C+C+M">Carey M. Lisse</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R">Robert Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Tan%2C+H">Hanjie Tan</a>, <a href="/search/astro-ph?searchtype=author&query=Copperwheat%2C+C">Chris Copperwheat</a>, <a href="/search/astro-ph?searchtype=author&query=Lin%2C+Z">Zhong-Yi Lin</a>, <a href="/search/astro-ph?searchtype=author&query=Morbidelli%2C+A">Alessandro Morbidelli</a>, <a href="/search/astro-ph?searchtype=author&query=Abe%2C+L">Lyu Abe</a>, <a href="/search/astro-ph?searchtype=author&query=Bendjoya%2C+P">Philippe Bendjoya</a>, <a href="/search/astro-ph?searchtype=author&query=Bauer%2C+J">James Bauer</a>, <a href="/search/astro-ph?searchtype=author&query=Burdge%2C+K+B">Kevin B. Burdge</a>, <a href="/search/astro-ph?searchtype=author&query=Coughlin%2C+M">Michael Coughlin</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Itoh%2C+R">Ryosuke Itoh</a>, <a href="/search/astro-ph?searchtype=author&query=Koss%2C+M">Michael Koss</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Maeno%2C+S">Syota Maeno</a>, <a href="/search/astro-ph?searchtype=author&query=Mamajek%2C+E+E">Eric E. Mamajek</a>, <a href="/search/astro-ph?searchtype=author&query=Marocco%2C+F">Federico Marocco</a>, <a href="/search/astro-ph?searchtype=author&query=Murata%2C+K">Katsuhiro Murata</a>, <a href="/search/astro-ph?searchtype=author&query=Rivet%2C+J">Jean-Pierre Rivet</a>, <a href="/search/astro-ph?searchtype=author&query=Sitko%2C+M+L">Michael L. Sitko</a>, <a href="/search/astro-ph?searchtype=author&query=Stern%2C+D">Daniel Stern</a>, <a href="/search/astro-ph?searchtype=author&query=Vernet%2C+D">David Vernet</a> , et al. (30 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1910.14004v4-abstract-short" style="display: inline;"> We present visible and near-infrared photometric and spectroscopic observations of interstellar object 2I/Borisov taken from 2019 September 10 to 2019 November 29 using the GROWTH, the APO ARC 3.5 m and the NASA/IRTF 3.0 m combined with post and pre-discovery observations of 2I obtained by ZTF from 2019 March 17 to 2019 May 5. Comparison with imaging of distant Solar System comets shows an object… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.14004v4-abstract-full').style.display = 'inline'; document.getElementById('1910.14004v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1910.14004v4-abstract-full" style="display: none;"> We present visible and near-infrared photometric and spectroscopic observations of interstellar object 2I/Borisov taken from 2019 September 10 to 2019 November 29 using the GROWTH, the APO ARC 3.5 m and the NASA/IRTF 3.0 m combined with post and pre-discovery observations of 2I obtained by ZTF from 2019 March 17 to 2019 May 5. Comparison with imaging of distant Solar System comets shows an object very similar to mildly active Solar System comets with an out-gassing rate of $\sim$10$^{27}$ mol/sec. The photometry, taken in filters spanning the visible and NIR range shows a gradual brightening trend of $\sim0.03$ mags/day since 2019 September 10 UTC for a reddish object becoming neutral in the NIR. The lightcurve from recent and pre-discovery data reveals a brightness trend suggesting the recent onset of significant H$_2$O sublimation with the comet being active with super volatiles such as CO at heliocentric distances $>$6 au consistent with its extended morphology. Using the advanced capability to significantly reduce the scattered light from the coma enabled by high-resolution NIR images from Keck adaptive optics taken on 2019 October 04, we estimate a diameter of 2I's nucleus of $\lesssim$1.4 km. We use the size estimates of 1I/'Oumuamua and 2I/Borisov to roughly estimate the slope of the ISO size-distribution resulting in a slope of $\sim$3.4$\pm$1.2, similar to Solar System comets and bodies produced from collisional equilibrium. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.14004v4-abstract-full').style.display = 'none'; document.getElementById('1910.14004v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 30 October, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">22 pages, 7 figures, 1 table. Accepted for publication in AJ on 12 May 2020</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1910.02967">arXiv:1910.02967</a> <span> [<a href="https://arxiv.org/pdf/1910.02967">pdf</a>, <a href="https://arxiv.org/format/1910.02967">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab4cf5">10.3847/1538-4357/ab4cf5 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> ZTF Early Observations of Type Ia Supernovae I: Properties of the 2018 Sample </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Yao%2C+Y">Yuhan Yao</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Bulla%2C+M">Mattia Bulla</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+D+A">Daniel A. Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Goobar%2C+A">Ariel Goobar</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P">Peter Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Dugas%2C+A">Alison Dugas</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">James D. Neill</a>, <a href="/search/astro-ph?searchtype=author&query=Rigault%2C+M">Michael Rigault</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">J. Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Dhawan%2C+S">Suhail Dhawan</a>, <a href="/search/astro-ph?searchtype=author&query=Feindt%2C+U">Ulrich Feindt</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gatkine%2C+P">Pradip Gatkine</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+L">Melissa L. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">T. Hung</a> , et al. (10 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1910.02967v1-abstract-short" style="display: inline;"> Early-time observations of Type Ia supernovae (SNe Ia) are essential to constrain their progenitor properties. In this paper, we present high-quality light curves of 127 SNe Ia discovered by the Zwicky Transient Facility (ZTF) in 2018. We describe our method to perform forced point spread function (PSF) photometry, which can be applied to other types of extragalactic transients. With a planned cad… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.02967v1-abstract-full').style.display = 'inline'; document.getElementById('1910.02967v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1910.02967v1-abstract-full" style="display: none;"> Early-time observations of Type Ia supernovae (SNe Ia) are essential to constrain their progenitor properties. In this paper, we present high-quality light curves of 127 SNe Ia discovered by the Zwicky Transient Facility (ZTF) in 2018. We describe our method to perform forced point spread function (PSF) photometry, which can be applied to other types of extragalactic transients. With a planned cadence of six observations per night ($3g+3r$), all of the 127 SNe Ia are detected in both $g$ and $r$ band more than 10\,d (in the rest frame) prior to the epoch of $g$-band maximum light. The redshifts of these objects range from $z=0.0181$ to 0.165; the median redshift is 0.074. Among the 127 SNe, 50 are detected at least 14\,d prior to maximum light (in the rest frame), with a subset of 9 objects being detected more than 17\,d before $g$-band peak. This is the largest sample of young SNe Ia collected to date; it can be used to study the shape and color evolution of the rising light curves in unprecedented detail. We discuss six peculiar events in this sample, including one 02cx-like event ZTF18abclfee (SN\,2018crl), one Ia-CSM SN ZTF18aaykjei (SN\,2018cxk), and four objects with possible super-Chandrasekhar mass progenitors: ZTF18abhpgje (SN\,2018eul), ZTF18abdpvnd (SN\,2018dvf), ZTF18aawpcel (SN\,2018cir) and ZTF18abddmrf (SN\,2018dsx). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.02967v1-abstract-full').style.display = 'none'; document.getElementById('1910.02967v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 October, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted by ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1906.05812">arXiv:1906.05812</a> <span> [<a href="https://arxiv.org/pdf/1906.05812">pdf</a>, <a href="https://arxiv.org/ps/1906.05812">ps</a>, <a href="https://arxiv.org/format/1906.05812">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/201936097">10.1051/0004-6361/201936097 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Type IIn supernova light-curve properties measured from an untargeted survey sample </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Nyholm%2C+A">A. Nyholm</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Tartaglia%2C+L">L. Tartaglia</a>, <a href="/search/astro-ph?searchtype=author&query=Taddia%2C+F">F. Taddia</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">A. V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">A. Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Howell%2C+D+A">D. A. Howell</a>, <a href="/search/astro-ph?searchtype=author&query=Karamehmetoglu%2C+E">E. Karamehmetoglu</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R">R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Leloudas%2C+G">G. Leloudas</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F">F. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Mor%C3%A5%2C+K">K. Mor氓</a>, <a href="/search/astro-ph?searchtype=author&query=Moriya%2C+T+J">T. J. Moriya</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E+O">E. O. Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Papadogiannakis%2C+S">S. Papadogiannakis</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R">R. Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Rebbapragada%2C+U">U. Rebbapragada</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">S. Schulze</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1906.05812v4-abstract-short" style="display: inline;"> We present a sample of supernovae Type IIn (SNe IIn) from the untargeted, magnitude-limited surveys of the Palomar Transient Factory (PTF) and its successor, the intermediate PTF (iPTF). The SNe IIn found and followed by the PTF/iPTF were used to select a sample of 42 events with useful constraints on the rise times as well as with available post-peak photometry. The sample SNe were discovered in… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1906.05812v4-abstract-full').style.display = 'inline'; document.getElementById('1906.05812v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1906.05812v4-abstract-full" style="display: none;"> We present a sample of supernovae Type IIn (SNe IIn) from the untargeted, magnitude-limited surveys of the Palomar Transient Factory (PTF) and its successor, the intermediate PTF (iPTF). The SNe IIn found and followed by the PTF/iPTF were used to select a sample of 42 events with useful constraints on the rise times as well as with available post-peak photometry. The sample SNe were discovered in 2009-2016 and have at least one low-resolution classification spectrum, as well as photometry from the P48 and P60 telescopes at Palomar Observatory. We study the light-curve properties of these SNe IIn using spline fits (for the peak and the declining portion) and template matching (for the rising portion). We find that the typical rise times are divided into fast and slow risers at $20\pm6$ d and $50\pm11$ d, respectively. The decline rates are possibly divided into two clusters, but this division has weak statistical significance. We find no significant correlation between the peak luminosity of SNe IIn and their rise times, but the more luminous SNe IIn are generally found to be more long-lasting. Slowly rising SNe IIn are generally found to decline slowly. The SNe in our sample were hosted by galaxies of absolute magnitude $-22 \lesssim M_g \lesssim -13$ mag. The K-corrections at light-curve peak of the SNe IIn in our sample are found to be within 0.2 mag for the observer's frame $r$-band, for SNe at redshifts $z < 0.25$. By applying K-corrections and also including ostensibly "superluminous" SNe IIn, we find that the peak magnitudes are $M_{\rm peak}^{r} = -19.18\pm1.32$ mag. We conclude that the occurrence of conspicuous light-curve bumps in SNe IIn, such as in iPTF13z, are limited to $1.4^{+14.6}_{-1.0} \%$ of the SNe IIn. We also investigate a possible sub-type of SNe IIn with a fast rise to a $\gtrsim 50$ d plateau followed by a slow, linear decline. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1906.05812v4-abstract-full').style.display = 'none'; document.getElementById('1906.05812v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 13 June, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Matches journal version. Table 2 on CDS. Durations in Fig. 13 corrected, conclusions unchanged. Abstract abridged. 33 pages, 22 figures, 7 tables</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 637, A73 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1904.11009">arXiv:1904.11009</a> <span> [<a href="https://arxiv.org/pdf/1904.11009">pdf</a>, <a href="https://arxiv.org/format/1904.11009">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab55ec">10.3847/1538-4357/ab55ec <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Evidence for Late-stage Eruptive Mass-loss in the Progenitor to SN2018gep, a Broad-lined Ic Supernova: Pre-explosion Emission and a Rapidly Rising Luminous Transient </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+D+A">Daniel A. Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">Steve Schulze</a>, <a href="/search/astro-ph?searchtype=author&query=Khatami%2C+D+K">David K. Khatami</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Ergon%2C+M">Mattias Ergon</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Corsi%2C+A">Alessandra Corsi</a>, <a href="/search/astro-ph?searchtype=author&query=Andreoni%2C+I">Igor Andreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">Cristina Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bright%2C+J+S">Joe S. Bright</a>, <a href="/search/astro-ph?searchtype=author&query=Burns%2C+E">Eric Burns</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Cunningham%2C+V">Virginia Cunningham</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">Richard Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Dugas%2C+A">Alison Dugas</a>, <a href="/search/astro-ph?searchtype=author&query=Fender%2C+R+P">Rob P. Fender</a>, <a href="/search/astro-ph?searchtype=author&query=Fransson%2C+C">Claes Fransson</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+A">Adam Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Hale%2C+D">David Hale</a> , et al. (25 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1904.11009v4-abstract-short" style="display: inline;"> We present detailed observations of ZTF18abukavn (SN2018gep), discovered in high-cadence data from the Zwicky Transient Facility as a rapidly rising ($1.4\pm0.1$ mag/hr) and luminous ($M_{g,\mathrm{peak}}=-20$ mag) transient. It is spectroscopically classified as a broad-lined stripped-envelope supernova (Ic-BL SN). The high peak luminosity ($L_{\mathrm{bol}} \gtrsim 3 \times 10^{44}$ erg… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.11009v4-abstract-full').style.display = 'inline'; document.getElementById('1904.11009v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.11009v4-abstract-full" style="display: none;"> We present detailed observations of ZTF18abukavn (SN2018gep), discovered in high-cadence data from the Zwicky Transient Facility as a rapidly rising ($1.4\pm0.1$ mag/hr) and luminous ($M_{g,\mathrm{peak}}=-20$ mag) transient. It is spectroscopically classified as a broad-lined stripped-envelope supernova (Ic-BL SN). The high peak luminosity ($L_{\mathrm{bol}} \gtrsim 3 \times 10^{44}$ erg $\mathrm{sec}^{-1}$), the short rise time ($t_{\mathrm{rise}}= 3$ days in $g$-band), and the blue colors at peak ($g-r\sim-0.4$) all resemble the high-redshift Ic-BL iPTF16asu, as well as several other unclassified fast transients. The early discovery of SN2018gep (within an hour of shock breakout) enabled an intensive spectroscopic campaign, including the highest-temperature ($T_{\mathrm{eff}}\gtrsim40,000$ K) spectra of a stripped-envelope SN. A retrospective search revealed luminous ($M_g \sim M_r \approx -14\,$mag) emission in the days to weeks before explosion, the first definitive detection of precursor emission for a Ic-BL. We find a limit on the isotropic gamma-ray energy release $E_\mathrm{纬,iso}<4.9 \times 10^{48}$ erg, a limit on X-ray emission $L_{\mathrm{X}} < 10^{40}\,$erg sec$^{-1}$, and a limit on radio emission $谓L_谓\lesssim 10^{37}\,$erg sec$^{-1}$. Taken together, we find that the early ($<10\,$days) data are best explained by shock breakout in a massive shell of dense circumstellar material ($0.02\,M_\odot$) at large radii ($3 \times 10^{14}\,$cm) that was ejected in eruptive pre-explosion mass-loss episodes. The late-time ($>10$ days) light curve requires an additional energy source, which could be the radioactive decay of Ni-56. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.11009v4-abstract-full').style.display = 'none'; document.getElementById('1904.11009v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 April, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted to ApJ on 1 Oct 2019. In this version, we made minor corrections and removed extraneous references</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1904.10973">arXiv:1904.10973</a> <span> [<a href="https://arxiv.org/pdf/1904.10973">pdf</a>, <a href="https://arxiv.org/format/1904.10973">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab3a38">10.3847/1538-4357/ab3a38 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A New Class of Changing-Look LINERs </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Frederick%2C+S">Sara Frederick</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">Suvi Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=van+Velzen%2C+S">Sjoert van Velzen</a>, <a href="/search/astro-ph?searchtype=author&query=Stern%2C+D">Daniel Stern</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">Shrinivas R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+U+C">U. Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">Tiara Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Kara%2C+E">Erin Kara</a>, <a href="/search/astro-ph?searchtype=author&query=Shupe%2C+D+L">David L. Shupe</a>, <a href="/search/astro-ph?searchtype=author&query=Ward%2C+C">Charlotte Ward</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">Richard Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Duev%2C+D+A">Dmitry A. Duev</a>, <a href="/search/astro-ph?searchtype=author&query=Feindt%2C+U">Ulrich Feindt</a>, <a href="/search/astro-ph?searchtype=author&query=Giomi%2C+M">Matteo Giomi</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">Thomas Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">James D. Neill</a> , et al. (6 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1904.10973v2-abstract-short" style="display: inline;"> We report the discovery of six active galactic nuclei (AGN) caught "turning on" during the first nine months of the Zwicky Transient Facility (ZTF) survey. The host galaxies were classified as LINERs by weak narrow forbidden line emission in their archival SDSS spectra, and detected by ZTF as nuclear transients. In five of the cases, we found via follow-up spectroscopy that they had transformed in… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.10973v2-abstract-full').style.display = 'inline'; document.getElementById('1904.10973v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.10973v2-abstract-full" style="display: none;"> We report the discovery of six active galactic nuclei (AGN) caught "turning on" during the first nine months of the Zwicky Transient Facility (ZTF) survey. The host galaxies were classified as LINERs by weak narrow forbidden line emission in their archival SDSS spectra, and detected by ZTF as nuclear transients. In five of the cases, we found via follow-up spectroscopy that they had transformed into broad-line AGN, reminiscent of the changing-look LINER iPTF 16bco. In one case, ZTF18aajupnt/AT2018dyk, follow-up HST UV and ground-based optical spectra revealed the transformation into a narrow-line Seyfert 1 (NLS1) with strong [Fe VII, X, XIV] and He II 4686 coronal lines. Swift monitoring observations of this source reveal bright UV emission that tracks the optical flare, accompanied by a luminous soft X-ray flare that peaks ~60 days later. Spitzer follow-up observations also detect a luminous mid-infrared flare implying a large covering fraction of dust. Archival light curves of the entire sample from CRTS, ATLAS, and ASAS-SN constrain the onset of the optical nuclear flaring from a prolonged quiescent state. Here we present the systematic selection and follow-up of this new class of changing-look LINERs, compare their properties to previously reported changing-look Seyfert galaxies, and conclude that they are a unique class of transients well-suited to test the uncertain physical processes associated with the LINER accretion state. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.10973v2-abstract-full').style.display = 'none'; document.getElementById('1904.10973v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 August, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 24 April, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Submitted to ApJ, 31 pages, 17 Figures (excluding Appendix due to file size constraints but will be available in electronic version)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1904.07857">arXiv:1904.07857</a> <span> [<a href="https://arxiv.org/pdf/1904.07857">pdf</a>, <a href="https://arxiv.org/format/1904.07857">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/2041-8213/ab2c05">10.3847/2041-8213/ab2c05 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Discovery of an intermediate-luminosity red transient in M51 and its likely dust-obscured, infrared-variable progenitor </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bond%2C+H+E">Howard E. Bond</a>, <a href="/search/astro-ph?searchtype=author&query=van+Dyk%2C+S+D">Schuyler D. van Dyk</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Bally%2C+J">John Bally</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Yao%2C+Y">Yuhan Yao</a>, <a href="/search/astro-ph?searchtype=author&query=Fruchter%2C+A">Andrew Fruchter</a>, <a href="/search/astro-ph?searchtype=author&query=Rubin%2C+D">David Rubin</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">Cristina Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Hicks%2C+E+K+S">Erin K. S. Hicks</a>, <a href="/search/astro-ph?searchtype=author&query=Malkan%2C+M+A">Matthew A. Malkan</a>, <a href="/search/astro-ph?searchtype=author&query=Andreoni%2C+I">Igor Andreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Buchheim%2C+R">Robert Buchheim</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">Richard Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Feeney%2C+M">Michael Feeney</a>, <a href="/search/astro-ph?searchtype=author&query=Frederick%2C+S">Sara Frederick</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Gehrz%2C+R+D">Robert D. Gehrz</a> , et al. (27 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1904.07857v2-abstract-short" style="display: inline;"> We present the discovery of an optical transient (OT) in Messier 51, designated M51 OT2019-1 (also ZTF19aadyppr, AT 2019abn, ATLAS19bzl), by the Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed luminosity of $M_r=-13$ ($谓L_谓=9\times10^6~L_{\odot}$), in the luminosity gap between novae and typical supernovae (SNe). Spectra during the outburst show a red continuum, Balmer emi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.07857v2-abstract-full').style.display = 'inline'; document.getElementById('1904.07857v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.07857v2-abstract-full" style="display: none;"> We present the discovery of an optical transient (OT) in Messier 51, designated M51 OT2019-1 (also ZTF19aadyppr, AT 2019abn, ATLAS19bzl), by the Zwicky Transient Facility (ZTF). The OT rose over 15 days to an observed luminosity of $M_r=-13$ ($谓L_谓=9\times10^6~L_{\odot}$), in the luminosity gap between novae and typical supernovae (SNe). Spectra during the outburst show a red continuum, Balmer emission with a velocity width of $\approx400$ km s$^{-1}$, Ca II and [Ca II] emission, and absorption features characteristic of an F-type supergiant. The spectra and multiband light curves are similar to the so-called "SN impostors" and intermediate-luminosity red transients (ILRTs). We directly identify the likely progenitor in archival Spitzer Space Telescope imaging with a $4.5~渭$m luminosity of $M_{[4.5]}\approx-12.2$ and a $[3.6]-[4.5]$ color redder than 0.74 mag, similar to those of the prototype ILRTs SN 2008S and NGC 300 OT2008-1. Intensive monitoring of M51 with Spitzer further reveals evidence for variability of the progenitor candidate at [4.5] in the years before the OT. The progenitor is not detected in pre-outburst Hubble Space Telescope optical and near-IR images. The optical colors during outburst combined with spectroscopic temperature constraints imply a higher reddening of $E(B-V)\approx0.7$ mag and higher intrinsic luminosity of $M_r\approx-14.9$ ($谓L_谓=5.3\times10^7~L_{\odot}$) near peak than seen in previous ILRT candidates. Moreover, the extinction estimate is higher on the rise than on the plateau, suggestive of an extended phase of circumstellar dust destruction. These results, enabled by the early discovery of M51 OT2019-1 and extensive pre-outburst archival coverage, offer new clues about the debated origins of ILRTs and may challenge the hypothesis that they arise from the electron-capture induced collapse of extreme asymptotic giant branch stars. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.07857v2-abstract-full').style.display = 'none'; document.getElementById('1904.07857v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 29 July, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 15 April, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 5 figures, published in ApJL</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> The Astrophysical Journal Letters, 880 (2019) L20 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.09262">arXiv:1903.09262</a> <span> [<a href="https://arxiv.org/pdf/1903.09262">pdf</a>, <a href="https://arxiv.org/ps/1903.09262">ps</a>, <a href="https://arxiv.org/format/1903.09262">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/2041-8213/ab218f">10.3847/2041-8213/ab218f <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> ZTF18aalrxas: A Type IIb Supernova from a very extended low-mass progenitor </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Ko%2C+H">H. Ko</a>, <a href="/search/astro-ph?searchtype=author&query=Dugas%2C+A">A. Dugas</a>, <a href="/search/astro-ph?searchtype=author&query=Ergon%2C+M">M. Ergon</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Bagdasaryan%2C+A">A. Bagdasaryan</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">C. Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Belicki%2C+J">J. Belicki</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E">E. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">K. De</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">R. Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Frederick%2C+S">S. Frederick</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">A. Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+D+A">D. A. Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Golkhou%2C+Z">Z. Golkhou</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M">M. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M">M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kowalski%2C+M">M. Kowalski</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">R. R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">A. A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">J. D. Neill</a> , et al. (9 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1903.09262v1-abstract-short" style="display: inline;"> We investigate ZTF18aalrxas, a double-peaked Type IIb core-collapse supernova (SN) discovered during science validation of the Zwicky Transient Facility (ZTF). ZTF18aalrxas was discovered while the optical emission was still rising towards the initial cooling peak (0.7 mag over 2 days). Our observations consist of multi-band (UV, optical) light-curves, and optical spectra spanning from… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.09262v1-abstract-full').style.display = 'inline'; document.getElementById('1903.09262v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.09262v1-abstract-full" style="display: none;"> We investigate ZTF18aalrxas, a double-peaked Type IIb core-collapse supernova (SN) discovered during science validation of the Zwicky Transient Facility (ZTF). ZTF18aalrxas was discovered while the optical emission was still rising towards the initial cooling peak (0.7 mag over 2 days). Our observations consist of multi-band (UV, optical) light-curves, and optical spectra spanning from $\approx0.7$ d to $\approx180$ d past the explosion. We use a Monte-Carlo based non-local thermodynamic equilibrium (NLTE) model, that simultanously reproduces both the $\rm ^{56}Ni$ powered bolometric light curve and our nebular spectrum. This model is used to constrain the synthesized radioactive nickel mass (0.17 $\mathrm{M}_{\odot}$) and the total ejecta mass (1.7 $\mathrm{M}_{\odot}$) of the SN. The cooling emission is modeled using semi-analytical extended envelope models to constrain the progenitor radius ($790-1050$ $\mathrm{R}_{\odot}$) at the time of explosion. Our nebular spectrum shows signs of interaction with a dense circumstellar medium (CSM), and this spetrum is modeled and analysed to constrain the amount of ejected oxygen ($0.3-0.5$ $\mathrm{M}_{\odot}$) and the total hydrogen mass ($\approx0.15$ $\mathrm{M}_{\odot}$) in the envelope of the progenitor. The oxygen mass of ZTF18aalrxas is consistent with a low ($12-13$ $\mathrm{M}_{\odot}$) Zero Age Main Sequence mass progenitor. The light curves and spectra of ZTF18aalrxas are not consistent with massive single star SN Type IIb progenitor models. The presence of an extended hydrogen envelope of low mass, the presence of a dense CSM, the derived ejecta mass, and the late-time oxygen emission can all be explained in a binary model scenario. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.09262v1-abstract-full').style.display = 'none'; document.getElementById('1903.09262v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 March, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">14 pages, 7 figures, submitted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.08128">arXiv:1903.08128</a> <span> [<a href="https://arxiv.org/pdf/1903.08128">pdf</a>, <a href="https://arxiv.org/format/1903.08128">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> </div> <p class="title is-5 mathjax"> The Dynamic Infrared Sky </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S">Scott Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Andreoni%2C+I">Igor Andreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Ashley%2C+M">Michael Ashley</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Frostig%2C+D">Danielle Frostig</a>, <a href="/search/astro-ph?searchtype=author&query=Furesz%2C+G">Gabor Furesz</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J">Jacob Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Hankins%2C+M">Matthew Hankins</a>, <a href="/search/astro-ph?searchtype=author&query=Helou%2C+G">George Helou</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R">Ryan Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Moore%2C+A">Anna Moore</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E">Eran Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Simcoe%2C+R">Rob Simcoe</a>, <a href="/search/astro-ph?searchtype=author&query=Sokoloski%2C+J">Jennifer Sokoloski</a>, <a href="/search/astro-ph?searchtype=author&query=Soon%2C+J">Jamie Soon</a>, <a href="/search/astro-ph?searchtype=author&query=Tinyanont%2C+S">Samaporn Tinyanont</a>, <a href="/search/astro-ph?searchtype=author&query=Travouillon%2C+T">Tony Travouillon</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1903.08128v1-abstract-short" style="display: inline;"> Opening up the dynamic infrared sky for systematic time-domain exploration would yield many scientific advances. Multi-messenger pursuits such as localizing gravitational waves from neutron star mergers and quantifying the nucleosynthetic yields require the infrared. Another multi-messenger endeavor that needs infrared surveyors is the study of the much-awaited supernova in our own Milky Way. Unde… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.08128v1-abstract-full').style.display = 'inline'; document.getElementById('1903.08128v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.08128v1-abstract-full" style="display: none;"> Opening up the dynamic infrared sky for systematic time-domain exploration would yield many scientific advances. Multi-messenger pursuits such as localizing gravitational waves from neutron star mergers and quantifying the nucleosynthetic yields require the infrared. Another multi-messenger endeavor that needs infrared surveyors is the study of the much-awaited supernova in our own Milky Way. Understanding shocks in novae, true rates of supernovae and stellar mergers are some other examples of stellar evolution and high energy physics wherein the answers are buried in the infrared. We discuss some of the challenges in the infrared and pathfinders to overcome them. We conclude with recommendations on both infrared discovery engines and infrared follow-up machines that would enable this field to flourish in the next decade. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.08128v1-abstract-full').style.display = 'none'; document.getElementById('1903.08128v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 March, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Astro2020 Science White Paper for Decadal Survey</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.05637">arXiv:1903.05637</a> <span> [<a href="https://arxiv.org/pdf/1903.05637">pdf</a>, <a href="https://arxiv.org/format/1903.05637">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab24de">10.3847/1538-4357/ab24de <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Discovery of Highly Blueshifted Broad Balmer and Metastable Helium Absorption Lines in a Tidal Disruption Event </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">T. Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Roth%2C+N">Nathaniel Roth</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">S. Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Veilleux%2C+S">S. Veilleux</a>, <a href="/search/astro-ph?searchtype=author&query=Van+Velzen%2C+S">Sjoert Van Velzen</a>, <a href="/search/astro-ph?searchtype=author&query=Gaskell%2C+C+M">C. Martin Gaskell</a>, <a href="/search/astro-ph?searchtype=author&query=Foley%2C+R+J">Ryan J. Foley</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">M. J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Brown%2C+J+S">J. S. Brown</a>, <a href="/search/astro-ph?searchtype=author&query=Siebert%2C+M+R">M. R. Siebert</a>, <a href="/search/astro-ph?searchtype=author&query=Frederick%2C+S">Sara Frederick</a>, <a href="/search/astro-ph?searchtype=author&query=Ward%2C+C">Charlotte Ward</a>, <a href="/search/astro-ph?searchtype=author&query=Gatkine%2C+P">Pradip Gatkine</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-yam%2C+A">Avishay Gal-yam</a>, <a href="/search/astro-ph?searchtype=author&query=Yang%2C+Y">Yi Yang</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">S. Schulze</a>, <a href="/search/astro-ph?searchtype=author&query=Dimitriadis%2C+G">G. Dimitriadis</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">Thomas Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Shupe%2C+D+L">David L. Shupe</a>, <a href="/search/astro-ph?searchtype=author&query=Rusholme%2C+B">Ben Rusholme</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Riddle%2C+R">Reed Riddle</a> , et al. (3 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1903.05637v1-abstract-short" style="display: inline;"> We report the discovery of non-stellar hydrogen Balmer and metastable helium absorption lines accompanying a transient, high-velocity (0.05$c$) broad absorption line (BAL) system in the optical spectra of the tidal disruption event (TDE) AT2018zr ($z=0.071$). In the HST UV spectra, absorption of high- and low-ionization lines are also present at this velocity, making AT2018zr resemble a low-ioniza… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.05637v1-abstract-full').style.display = 'inline'; document.getElementById('1903.05637v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.05637v1-abstract-full" style="display: none;"> We report the discovery of non-stellar hydrogen Balmer and metastable helium absorption lines accompanying a transient, high-velocity (0.05$c$) broad absorption line (BAL) system in the optical spectra of the tidal disruption event (TDE) AT2018zr ($z=0.071$). In the HST UV spectra, absorption of high- and low-ionization lines are also present at this velocity, making AT2018zr resemble a low-ionization broad absorption line (LoBAL) QSO. We conclude that these transient absorption features are more likely to arise in fast outflows produced by the TDE than absorbed by the unbound debris. In accordance with the outflow picture, we are able to reproduce the flat-topped H$伪$ emission in a spherically expanding medium, without invoking the typical prescription of an elliptical disk. We also report the appearance of narrow ($\sim$1000~km~s$^{-1}$) NIII$位$4640, HeII$\lambda4686$, H$伪$, and H$尾$, emission in the late-time optical spectra of AT2018zr, which may be a result of UV continuum hardening at late time as observed by Swift. Including AT2018zr, we find a high association rate (3 out of 4) of BALs in the UV spectra of TDEs. This suggests that outflows may be ubiquitous among TDEs and may be less sensitive to viewing angle effects compared to QSO outflows. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.05637v1-abstract-full').style.display = 'none'; document.getElementById('1903.05637v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 13 March, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">20 pages, 11 figures, submitted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.04553">arXiv:1903.04553</a> <span> [<a href="https://arxiv.org/pdf/1903.04553">pdf</a>, <a href="https://arxiv.org/ps/1903.04553">ps</a>, <a href="https://arxiv.org/format/1903.04553">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Cosmology and Nongalactic Astrophysics">astro-ph.CO</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> </div> <p class="title is-5 mathjax"> Gravity and Light: Combining Gravitational Wave and Electromagnetic Observations in the 2020s </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Foley%2C+R+J">R. J. Foley</a>, <a href="/search/astro-ph?searchtype=author&query=Alexander%2C+K+D">K. D. Alexander</a>, <a href="/search/astro-ph?searchtype=author&query=Andreoni%2C+I">I. Andreoni</a>, <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">I. Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=Auchettl%2C+K">K. Auchettl</a>, <a href="/search/astro-ph?searchtype=author&query=Barnes%2C+J">J. Barnes</a>, <a href="/search/astro-ph?searchtype=author&query=Baym%2C+G">G. Baym</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">E. C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Beloborodov%2C+A+M">A. M. Beloborodov</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Blakeslee%2C+J+P">J. P. Blakeslee</a>, <a href="/search/astro-ph?searchtype=author&query=Brady%2C+P+R">P. R. Brady</a>, <a href="/search/astro-ph?searchtype=author&query=Branchesi%2C+M">M. Branchesi</a>, <a href="/search/astro-ph?searchtype=author&query=Brown%2C+J+S">J. S. Brown</a>, <a href="/search/astro-ph?searchtype=author&query=Butler%2C+N">N. Butler</a>, <a href="/search/astro-ph?searchtype=author&query=Cantiello%2C+M">M. Cantiello</a>, <a href="/search/astro-ph?searchtype=author&query=Chornock%2C+R">R. Chornock</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D+O">D. O. Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Cooke%2C+J">J. Cooke</a>, <a href="/search/astro-ph?searchtype=author&query=Coppejans%2C+D+L">D. L. Coppejans</a>, <a href="/search/astro-ph?searchtype=author&query=Corsi%2C+A">A. Corsi</a>, <a href="/search/astro-ph?searchtype=author&query=Couch%2C+S+M">S. M. Couch</a>, <a href="/search/astro-ph?searchtype=author&query=Coughlin%2C+M+W">M. W. Coughlin</a>, <a href="/search/astro-ph?searchtype=author&query=Coulter%2C+D+A">D. A. Coulter</a>, <a href="/search/astro-ph?searchtype=author&query=Cowperthwaite%2C+P+S">P. S. Cowperthwaite</a> , et al. (88 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1903.04553v1-abstract-short" style="display: inline;"> As of today, we have directly detected exactly one source in both gravitational waves (GWs) and electromagnetic (EM) radiation, the binary neutron star merger GW170817, its associated gamma-ray burst GRB170817A, and the subsequent kilonova SSS17a/AT 2017gfo. Within ten years, we will detect hundreds of events, including new classes of events such as neutron-star-black-hole mergers, core-collapse s… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.04553v1-abstract-full').style.display = 'inline'; document.getElementById('1903.04553v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.04553v1-abstract-full" style="display: none;"> As of today, we have directly detected exactly one source in both gravitational waves (GWs) and electromagnetic (EM) radiation, the binary neutron star merger GW170817, its associated gamma-ray burst GRB170817A, and the subsequent kilonova SSS17a/AT 2017gfo. Within ten years, we will detect hundreds of events, including new classes of events such as neutron-star-black-hole mergers, core-collapse supernovae, and almost certainly something completely unexpected. As we build this sample, we will explore exotic astrophysical topics ranging from nucleosynthesis, stellar evolution, general relativity, high-energy astrophysics, nuclear matter, to cosmology. The discovery potential is extraordinary, and investments in this area will yield major scientific breakthroughs. Here we outline some of the most exciting scientific questions that can be answered by combining GW and EM observations. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.04553v1-abstract-full').style.display = 'none'; document.getElementById('1903.04553v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 March, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">submitted to Astro2020</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.08526">arXiv:1902.08526</a> <span> [<a href="https://arxiv.org/pdf/1902.08526">pdf</a>, <a href="https://arxiv.org/format/1902.08526">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/201935344">10.1051/0004-6361/201935344 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A Fully Automated Integral Field Spectrograph Pipeline for the SEDMachine: pysedm </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Rigault%2C+M">M. Rigault</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">J. D. Neill</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Dugas%2C+A">A. Dugas</a>, <a href="/search/astro-ph?searchtype=author&query=Feeney%2C+M">M. Feeney</a>, <a href="/search/astro-ph?searchtype=author&query=Walters%2C+R">R. Walters</a>, <a href="/search/astro-ph?searchtype=author&query=Copin%2C+Y">Y. Copin</a>, <a href="/search/astro-ph?searchtype=author&query=Brinnel%2C+V">V. Brinnel</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">J. Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.08526v1-abstract-short" style="display: inline;"> Current time domain facilities are discovering hundreds of new galactic and extra-galactic transients every week. Classifying the ever-increasing number of transients is challenging, yet crucial to further our understanding of their nature, discover new classes, or ensuring sample purity, for instance, for Supernova Ia cosmology. The Zwicky Transient Facility is one example of such a survey. In ad… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.08526v1-abstract-full').style.display = 'inline'; document.getElementById('1902.08526v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.08526v1-abstract-full" style="display: none;"> Current time domain facilities are discovering hundreds of new galactic and extra-galactic transients every week. Classifying the ever-increasing number of transients is challenging, yet crucial to further our understanding of their nature, discover new classes, or ensuring sample purity, for instance, for Supernova Ia cosmology. The Zwicky Transient Facility is one example of such a survey. In addition, it has a dedicated very-low resolution spectrograph, the SEDMachine, operating on the Palomar 60-inch telescope. This spectrograph's primary aim is object classification. In practice most, if not all, transients of interest brighter than ~19 mag are typed. This corresponds to approximately 10 to 15 targets a night. In this paper, we present a fully automated pipeline for the SEDMachine. This pipeline has been designed to be fast, robust, stable and extremely flexible. pysedm enables the fully automated spectral extraction of a targeted point source object in less than 5 minutes after the end of the exposure. The spectral color calibration is accurate at the few percent level. In the 19 weeks since pysedm entered production in early August of 2018, we have classified, among other objects, about 400 Type Ia supernovae and 140 Type II supernovae. We conclude that low resolution, fully automated spectrographs such as the `SEDMachine with pysedm' installed on 2-m class telescopes within the southern hemisphere could allow us to automatically and simultaneously type and obtain a redshift for most (if not all) bright transients detected by LSST within z<0.2, notably potentially all Type Ia Supernovae. In comparison to the current SEDM design, this would require higher spectral resolution (R~1000) and slightly improved throughput. With this perspective in mind, pysedm has been designed to easily be adaptable to any IFU-like spectrograph (see https://github.com/MickaelRigault/pysedm). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.08526v1-abstract-full').style.display = 'none'; document.getElementById('1902.08526v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Submitted to Astronomy and Astrophysics</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 627, A115 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.01945">arXiv:1902.01945</a> <span> [<a href="https://arxiv.org/pdf/1902.01945">pdf</a>, <a href="https://arxiv.org/format/1902.01945">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/ab006c">10.1088/1538-3873/ab006c <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Zwicky Transient Facility: Science Objectives </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">Cristina Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bodewits%2C+D">Dennis Bodewits</a>, <a href="/search/astro-ph?searchtype=author&query=Bolin%2C+B">Bryce Bolin</a>, <a href="/search/astro-ph?searchtype=author&query=Brady%2C+P+R">Patrick R. Brady</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Chang%2C+C">Chan-Kao Chang</a>, <a href="/search/astro-ph?searchtype=author&query=Coughlin%2C+M+W">Michael W. Coughlin</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Eadie%2C+G">Gwendolyn Eadie</a>, <a href="/search/astro-ph?searchtype=author&query=Farnham%2C+T+L">Tony L. Farnham</a>, <a href="/search/astro-ph?searchtype=author&query=Feindt%2C+U">Ulrich Feindt</a>, <a href="/search/astro-ph?searchtype=author&query=Franckowiak%2C+A">Anna Franckowiak</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-yam%2C+A">Avishay Gal-yam</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">Suvi Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Ghosh%2C+S">Shaon Ghosh</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+D+A">Daniel A. Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Golkhou%2C+V+Z">V. Zach Golkhou</a>, <a href="/search/astro-ph?searchtype=author&query=Goobar%2C+A">Ariel Goobar</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a> , et al. (92 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.01945v1-abstract-short" style="display: inline;"> The Zwicky Transient Facility (ZTF), a public-private enterprise, is a new time domain survey employing a dedicated camera on the Palomar 48-inch Schmidt telescope with a 47 deg$^2$ field of view and 8 second readout time. It is well positioned in the development of time domain astronomy, offering operations at 10% of the scale and style of the Large Synoptic Survey Telescope (LSST) with a single… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01945v1-abstract-full').style.display = 'inline'; document.getElementById('1902.01945v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.01945v1-abstract-full" style="display: none;"> The Zwicky Transient Facility (ZTF), a public-private enterprise, is a new time domain survey employing a dedicated camera on the Palomar 48-inch Schmidt telescope with a 47 deg$^2$ field of view and 8 second readout time. It is well positioned in the development of time domain astronomy, offering operations at 10% of the scale and style of the Large Synoptic Survey Telescope (LSST) with a single 1-m class survey telescope. The public surveys will cover the observable northern sky every three nights in g and r filters and the visible Galactic plane every night in g and r. Alerts generated by these surveys are sent in real time to brokers. A consortium of universities which provided funding ("partnership") are undertaking several boutique surveys. The combination of these surveys producing one million alerts per night allows for exploration of transient and variable astrophysical phenomena brighter than r $\sim$ 20.5 on timescales of minutes to years. We describe the primary science objectives driving ZTF including the physics of supernovae and relativistic explosions, multi-messenger astrophysics, supernova cosmology, active galactic nuclei and tidal disruption events, stellar variability, and Solar System objects. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01945v1-abstract-full').style.display = 'none'; document.getElementById('1902.01945v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">26 pages, 7 figures, Published in PASP Focus Issue on the Zwicky Transient Facility</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.01936">arXiv:1902.01936</a> <span> [<a href="https://arxiv.org/pdf/1902.01936">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/aaf3fa">10.1088/1538-3873/aaf3fa <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Machine Learning for the Zwicky Transient Facility </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Mahabal%2C+A">Ashish Mahabal</a>, <a href="/search/astro-ph?searchtype=author&query=Rebbapragada%2C+U">Umaa Rebbapragada</a>, <a href="/search/astro-ph?searchtype=author&query=Walters%2C+R">Richard Walters</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=van+Roestel%2C+J">Jan van Roestel</a>, <a href="/search/astro-ph?searchtype=author&query=Ye%2C+Q">Quan-Zhi Ye</a>, <a href="/search/astro-ph?searchtype=author&query=Biswas%2C+R">Rahul Biswas</a>, <a href="/search/astro-ph?searchtype=author&query=Burdge%2C+K">Kevin Burdge</a>, <a href="/search/astro-ph?searchtype=author&query=Chang%2C+C">Chan-Kao Chang</a>, <a href="/search/astro-ph?searchtype=author&query=Duev%2C+D+A">Dmitry A. Duev</a>, <a href="/search/astro-ph?searchtype=author&query=Golkhou%2C+V+Z">V. Zach Golkhou</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">Jakob Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Ward%2C+C">Charlotte Ward</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S">Scott Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Branton%2C+D">Doug Branton</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B">Brian Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Cannella%2C+C">Chris Cannella</a>, <a href="/search/astro-ph?searchtype=author&query=Connolly%2C+A">Andrew Connolly</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">Richard Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Feindt%2C+U">Ulrich Feindt</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">Tiara Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a> , et al. (25 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.01936v1-abstract-short" style="display: inline;"> The Zwicky Transient Facility is a large optical survey in multiple filters producing hundreds of thousands of transient alerts per night. We describe here various machine learning (ML) implementations and plans to make the maximal use of the large data set by taking advantage of the temporal nature of the data, and further combining it with other data sets. We start with the initial steps of sepa… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01936v1-abstract-full').style.display = 'inline'; document.getElementById('1902.01936v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.01936v1-abstract-full" style="display: none;"> The Zwicky Transient Facility is a large optical survey in multiple filters producing hundreds of thousands of transient alerts per night. We describe here various machine learning (ML) implementations and plans to make the maximal use of the large data set by taking advantage of the temporal nature of the data, and further combining it with other data sets. We start with the initial steps of separating bogus candidates from real ones, separating stars and galaxies, and go on to the classification of real objects into various classes. Besides the usual methods (e.g., based on features extracted from light curves) we also describe early plans for alternate methods including the use of domain adaptation, and deep learning. In a similar fashion we describe efforts to detect fast moving asteroids. We also describe the use of the Zooniverse platform for helping with classifications through the creation of training samples, and active learning. Finally we mention the synergistic aspects of ZTF and LSST from the ML perspective. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01936v1-abstract-full').style.display = 'none'; document.getElementById('1902.01936v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Published in PASP Focus Issue on the Zwicky Transient Facility (doi: 10.1088/1538-3873/aaf3fa). 14 Pages, 8 Figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.01932">arXiv:1902.01932</a> <span> [<a href="https://arxiv.org/pdf/1902.01932">pdf</a>, <a href="https://arxiv.org/format/1902.01932">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/aaecbe">10.1088/1538-3873/aaecbe <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Zwicky Transient Facility: System Overview, Performance, and First Results </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">Shrinivas R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R">Richard Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Smith%2C+R+M">Roger M. Smith</a>, <a href="/search/astro-ph?searchtype=author&query=Riddle%2C+R">Reed Riddle</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Helou%2C+G">George Helou</a>, <a href="/search/astro-ph?searchtype=author&query=Prince%2C+T+A">Thomas A. Prince</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Barbarino%2C+C">C. Barbarino</a>, <a href="/search/astro-ph?searchtype=author&query=Barlow%2C+T">Tom Barlow</a>, <a href="/search/astro-ph?searchtype=author&query=Bauer%2C+J">James Bauer</a>, <a href="/search/astro-ph?searchtype=author&query=Beck%2C+R">Ron Beck</a>, <a href="/search/astro-ph?searchtype=author&query=Belicki%2C+J">Justin Belicki</a>, <a href="/search/astro-ph?searchtype=author&query=Biswas%2C+R">Rahul Biswas</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bodewits%2C+D">Dennis Bodewits</a>, <a href="/search/astro-ph?searchtype=author&query=Bolin%2C+B">Bryce Bolin</a>, <a href="/search/astro-ph?searchtype=author&query=Brinnel%2C+V">Valery Brinnel</a>, <a href="/search/astro-ph?searchtype=author&query=Brooke%2C+T">Tim Brooke</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B">Brian Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Bulla%2C+M">Mattia Bulla</a>, <a href="/search/astro-ph?searchtype=author&query=Burruss%2C+R">Rick Burruss</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a> , et al. (91 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.01932v1-abstract-short" style="display: inline;"> The Zwicky Transient Facility (ZTF) is a new optical time-domain survey that uses the Palomar 48-inch Schmidt telescope. A custom-built wide-field camera provides a 47 deg$^2$ field of view and 8 second readout time, yielding more than an order of magnitude improvement in survey speed relative to its predecessor survey, the Palomar Transient Factory (PTF). We describe the design and implementation… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01932v1-abstract-full').style.display = 'inline'; document.getElementById('1902.01932v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.01932v1-abstract-full" style="display: none;"> The Zwicky Transient Facility (ZTF) is a new optical time-domain survey that uses the Palomar 48-inch Schmidt telescope. A custom-built wide-field camera provides a 47 deg$^2$ field of view and 8 second readout time, yielding more than an order of magnitude improvement in survey speed relative to its predecessor survey, the Palomar Transient Factory (PTF). We describe the design and implementation of the camera and observing system. The ZTF data system at the Infrared Processing and Analysis Center provides near-real-time reduction to identify moving and varying objects. We outline the analysis pipelines, data products, and associated archive. Finally, we present on-sky performance analysis and first scientific results from commissioning and the early survey. ZTF's public alert stream will serve as a useful precursor for that of the Large Synoptic Survey Telescope. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01932v1-abstract-full').style.display = 'none'; document.getElementById('1902.01932v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Published in PASP Focus Issue on the Zwicky Transient Facility (https://dx.doi.org/10.1088/1538-3873/aaecbe). 21 Pages, 12 Figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Publications of the Astronomical Society of the Pacific, Volume 131, Issue 995, pp. 018002 (2019) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.01872">arXiv:1902.01872</a> <span> [<a href="https://arxiv.org/pdf/1902.01872">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/aae8ac">10.1088/1538-3873/aae8ac <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Zwicky Transient Facility: Data Processing, Products, and Archive </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Rusholme%2C+B">Ben Rusholme</a>, <a href="/search/astro-ph?searchtype=author&query=Shupe%2C+D+L">David L. Shupe</a>, <a href="/search/astro-ph?searchtype=author&query=Groom%2C+S">Steven Groom</a>, <a href="/search/astro-ph?searchtype=author&query=Surace%2C+J">Jason Surace</a>, <a href="/search/astro-ph?searchtype=author&query=Jackson%2C+E">Edward Jackson</a>, <a href="/search/astro-ph?searchtype=author&query=Monkewitz%2C+S">Serge Monkewitz</a>, <a href="/search/astro-ph?searchtype=author&query=Beck%2C+R">Ron Beck</a>, <a href="/search/astro-ph?searchtype=author&query=Flynn%2C+D">David Flynn</a>, <a href="/search/astro-ph?searchtype=author&query=Terek%2C+S">Scott Terek</a>, <a href="/search/astro-ph?searchtype=author&query=Landry%2C+W">Walter Landry</a>, <a href="/search/astro-ph?searchtype=author&query=Hacopians%2C+E">Eugean Hacopians</a>, <a href="/search/astro-ph?searchtype=author&query=Desai%2C+V">Vandana Desai</a>, <a href="/search/astro-ph?searchtype=author&query=Howell%2C+J">Justin Howell</a>, <a href="/search/astro-ph?searchtype=author&query=Brooke%2C+T">Tim Brooke</a>, <a href="/search/astro-ph?searchtype=author&query=Imel%2C+D">David Imel</a>, <a href="/search/astro-ph?searchtype=author&query=Wachter%2C+S">Stefanie Wachter</a>, <a href="/search/astro-ph?searchtype=author&query=Ye%2C+Q">Quan-Zhi Ye</a>, <a href="/search/astro-ph?searchtype=author&query=Lin%2C+H">Hsing-Wen Lin</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Cunningham%2C+V">Virginia Cunningham</a>, <a href="/search/astro-ph?searchtype=author&query=Rebbapragada%2C+U">Umaa Rebbapragada</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B">Brian Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a> , et al. (24 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.01872v1-abstract-short" style="display: inline;"> The Zwicky Transient Facility (ZTF) is a new robotic time-domain survey currently in progress using the Palomar 48-inch Schmidt Telescope. ZTF uses a 47 square degree field with a 600 megapixel camera to scan the entire northern visible sky at rates of ~3760 square degrees/hour to median depths of g ~ 20.8 and r ~ 20.6 mag (AB, 5sigma in 30 sec). We describe the Science Data System that is housed… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01872v1-abstract-full').style.display = 'inline'; document.getElementById('1902.01872v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.01872v1-abstract-full" style="display: none;"> The Zwicky Transient Facility (ZTF) is a new robotic time-domain survey currently in progress using the Palomar 48-inch Schmidt Telescope. ZTF uses a 47 square degree field with a 600 megapixel camera to scan the entire northern visible sky at rates of ~3760 square degrees/hour to median depths of g ~ 20.8 and r ~ 20.6 mag (AB, 5sigma in 30 sec). We describe the Science Data System that is housed at IPAC, Caltech. This comprises the data-processing pipelines, alert production system, data archive, and user interfaces for accessing and analyzing the products. The realtime pipeline employs a novel image-differencing algorithm, optimized for the detection of point source transient events. These events are vetted for reliability using a machine-learned classifier and combined with contextual information to generate data-rich alert packets. The packets become available for distribution typically within 13 minutes (95th percentile) of observation. Detected events are also linked to generate candidate moving-object tracks using a novel algorithm. Objects that move fast enough to streak in the individual exposures are also extracted and vetted. The reconstructed astrometric accuracy per science image with respect to Gaia is typically 45 to 85 milliarcsec. This is the RMS per axis on the sky for sources extracted with photometric S/N >= 10. The derived photometric precision (repeatability) at bright unsaturated fluxes varies between 8 and 25 millimag. Photometric calibration accuracy with respect to Pan-STARRS1 is generally better than 2%. The products support a broad range of scientific applications: fast and young supernovae, rare flux transients, variable stars, eclipsing binaries, variability from active galactic nuclei, counterparts to gravitational wave sources, a more complete census of Type Ia supernovae, and Solar System objects. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01872v1-abstract-full').style.display = 'none'; document.getElementById('1902.01872v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">30 pages, 16 figures, Published in PASP Focus Issue on the Zwicky Transient Facility (doi: 10.1088/1538-3873/aae8ac)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1901.07281">arXiv:1901.07281</a> <span> [<a href="https://arxiv.org/pdf/1901.07281">pdf</a>, <a href="https://arxiv.org/format/1901.07281">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/201935097">10.1051/0004-6361/201935097 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Full orbital solution for the binary system in the northern Galactic disc microlensing event Gaia16aye </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Wyrzykowski%2C+%C5%81">艁ukasz Wyrzykowski</a>, <a href="/search/astro-ph?searchtype=author&query=Mr%C3%B3z%2C+P">P. Mr贸z</a>, <a href="/search/astro-ph?searchtype=author&query=Rybicki%2C+K+A">K. A. Rybicki</a>, <a href="/search/astro-ph?searchtype=author&query=Gromadzki%2C+M">M. Gromadzki</a>, <a href="/search/astro-ph?searchtype=author&query=Ko%C5%82aczkowski%2C+Z">Z. Ko艂aczkowski</a>, <a href="/search/astro-ph?searchtype=author&query=Zieli%C5%84ski%2C+M">M. Zieli艅ski</a>, <a href="/search/astro-ph?searchtype=author&query=Zieli%C5%84ski%2C+P">P. Zieli艅ski</a>, <a href="/search/astro-ph?searchtype=author&query=Britavskiy%2C+N">N. Britavskiy</a>, <a href="/search/astro-ph?searchtype=author&query=Gomboc%2C+A">A. Gomboc</a>, <a href="/search/astro-ph?searchtype=author&query=Sokolovsky%2C+K">K. Sokolovsky</a>, <a href="/search/astro-ph?searchtype=author&query=Hodgkin%2C+S+T">S. T. Hodgkin</a>, <a href="/search/astro-ph?searchtype=author&query=Abe%2C+L">L. Abe</a>, <a href="/search/astro-ph?searchtype=author&query=Aldi%2C+G+F">G. F. Aldi</a>, <a href="/search/astro-ph?searchtype=author&query=AlMannaei%2C+A">A. AlMannaei</a>, <a href="/search/astro-ph?searchtype=author&query=Altavilla%2C+G">G. Altavilla</a>, <a href="/search/astro-ph?searchtype=author&query=Qasim%2C+A+A">A. Al Qasim</a>, <a href="/search/astro-ph?searchtype=author&query=Anupama%2C+G+C">G. C. Anupama</a>, <a href="/search/astro-ph?searchtype=author&query=Awiphan%2C+S">S. Awiphan</a>, <a href="/search/astro-ph?searchtype=author&query=Bachelet%2C+E">E. Bachelet</a>, <a href="/search/astro-ph?searchtype=author&query=Bak%C4%B1s%2C+V">V. Bak谋s</a>, <a href="/search/astro-ph?searchtype=author&query=Baker%2C+S">S. Baker</a>, <a href="/search/astro-ph?searchtype=author&query=Bartlett%2C+S">S. Bartlett</a>, <a href="/search/astro-ph?searchtype=author&query=Bendjoya%2C+P">P. Bendjoya</a>, <a href="/search/astro-ph?searchtype=author&query=Benson%2C+K">K. Benson</a>, <a href="/search/astro-ph?searchtype=author&query=Bikmaev%2C+I+F">I. F. Bikmaev</a> , et al. (160 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1901.07281v2-abstract-short" style="display: inline;"> Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I=12 mag, and it was covered in great detail with almost 25,000 data points gathered by a network of telescopes. We presen… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.07281v2-abstract-full').style.display = 'inline'; document.getElementById('1901.07281v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.07281v2-abstract-full" style="display: none;"> Gaia16aye was a binary microlensing event discovered in the direction towards the northern Galactic disc and was one of the first microlensing events detected and alerted to by the Gaia space mission. Its light curve exhibited five distinct brightening episodes, reaching up to I=12 mag, and it was covered in great detail with almost 25,000 data points gathered by a network of telescopes. We present the photometric and spectroscopic follow-up covering 500 days of the event evolution. We employed a full Keplerian binary orbit microlensing model combined with the motion of Earth and Gaia around the Sun to reproduce the complex light curve. The photometric data allowed us to solve the microlensing event entirely and to derive the complete and unique set of orbital parameters of the binary lensing system. We also report on the detection of the first-ever microlensing space-parallax between the Earth and Gaia located at L2. The properties of the binary system were derived from microlensing parameters, and we found that the system is composed of two main-sequence stars with masses 0.57$\pm$0.05 $M_\odot$ and 0.36$\pm$0.03 $M_\odot$ at 780 pc, with an orbital period of 2.88 years and an eccentricity of 0.30. We also predict the astrometric microlensing signal for this binary lens as it will be seen by Gaia as well as the radial velocity curve for the binary system. Events such as Gaia16aye indicate the potential for the microlensing method of probing the mass function of dark objects, including black holes, in directions other than that of the Galactic bulge. This case also emphasises the importance of long-term time-domain coordinated observations that can be made with a network of heterogeneous telescopes. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.07281v2-abstract-full').style.display = 'none'; document.getElementById('1901.07281v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 28 October, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 22 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">accepted for publication in A&A, 24 pages, 10 figures, tables with the data will be available electronically</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 633, A98 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1901.00874">arXiv:1901.00874</a> <span> [<a href="https://arxiv.org/pdf/1901.00874">pdf</a>, <a href="https://arxiv.org/format/1901.00874">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/2041-8213/ab0aec">10.3847/2041-8213/ab0aec <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> ZTF 18aaqeasu (SN 2018byg): A Massive Helium-shell Double Detonation on a Sub-Chandrasekhar Mass White Dwarf </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Polin%2C+A">Abigail Polin</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">Peter E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Bildsten%2C+L">Lars Bildsten</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Burdge%2C+K+B">Kevin B. Burdge</a>, <a href="/search/astro-ph?searchtype=author&query=Cannella%2C+C">Christopher Cannella</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R+G">Richard G. Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Feeney%2C+M">Michael Feeney</a>, <a href="/search/astro-ph?searchtype=author&query=Hale%2C+D">David Hale</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">Anna Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">Adam A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Patterson%2C+M+T">Maria T. Patterson</a>, <a href="/search/astro-ph?searchtype=author&query=Rebbapragada%2C+U">Umaa Rebbapragada</a>, <a href="/search/astro-ph?searchtype=author&query=Riddle%2C+R+L">Reed L. Riddle</a> , et al. (2 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1901.00874v1-abstract-short" style="display: inline;"> The detonation of a helium shell on a white dwarf has been proposed as a possible explosion triggering mechanism for Type Ia supernovae. Here, we report ZTF 18aaqeasu (SN 2018byg/ATLAS 18pqq), a peculiar Type I supernova, consistent with being a helium-shell double-detonation. With a rise time of $\approx 18$ days from explosion, the transient reached a peak absolute magnitude of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00874v1-abstract-full').style.display = 'inline'; document.getElementById('1901.00874v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.00874v1-abstract-full" style="display: none;"> The detonation of a helium shell on a white dwarf has been proposed as a possible explosion triggering mechanism for Type Ia supernovae. Here, we report ZTF 18aaqeasu (SN 2018byg/ATLAS 18pqq), a peculiar Type I supernova, consistent with being a helium-shell double-detonation. With a rise time of $\approx 18$ days from explosion, the transient reached a peak absolute magnitude of $M_R \approx -18.2$ mag, exhibiting a light curve akin to sub-luminous SN 1991bg-like Type Ia supernovae, albeit with an unusually steep increase in brightness within a week from explosion. Spectra taken near peak light exhibit prominent Si absorption features together with an unusually red color ($g-r \approx 2$ mag) arising from nearly complete line blanketing of flux blue-wards of 5000 脜. This behavior is unlike any previously observed thermonuclear transient. Nebular phase spectra taken at and after $\approx 30$ days from peak light reveal evidence of a thermonuclear detonation event dominated by Fe-group nucleosynthesis. We show that the peculiar properties of ZTF 18aaqeasu are consistent with the detonation of a massive ($\approx 0.15$ M$_\odot$) helium shell on a sub-Chandrasekhar mass ($\approx 0.75$ M$_\odot$) white dwarf after including mixing of $\approx 0.2$ M$_\odot$ of material in the outer ejecta. These observations provide evidence of a likely rare class of thermonuclear supernovae arising from detonations of massive helium shells. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00874v1-abstract-full').style.display = 'none'; document.getElementById('1901.00874v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 3 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">10 pages, 6 figures. Submitted to ApJL</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1901.00872">arXiv:1901.00872</a> <span> [<a href="https://arxiv.org/pdf/1901.00872">pdf</a>, <a href="https://arxiv.org/format/1901.00872">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab4185">10.3847/1538-4357/ab4185 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Host Galaxies of Type Ic and Broad-lined Type Ic Supernovae from the Palomar Transient Factory: Implication for Jet Production </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Modjaz%2C+M">Maryam Modjaz</a>, <a href="/search/astro-ph?searchtype=author&query=Bianco%2C+F+B">Federica B. Bianco</a>, <a href="/search/astro-ph?searchtype=author&query=Siwek%2C+M">Magdalena Siwek</a>, <a href="/search/astro-ph?searchtype=author&query=Huang%2C+S">Shan Huang</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Fierroz%2C+D">David Fierroz</a>, <a href="/search/astro-ph?searchtype=author&query=Liu%2C+Y">Yu-Qian Liu</a>, <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">Iair Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+B+S">Bradley S. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">Alexei V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Schulze%2C+S">Steve Schulze</a>, <a href="/search/astro-ph?searchtype=author&query=Taggart%2C+K">Kirsty Taggart</a>, <a href="/search/astro-ph?searchtype=author&query=Zhen%2C+W">Weikang Zhen</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1901.00872v1-abstract-short" style="display: inline;"> Unlike the ordinary supernovae (SNe) some of which are hydrogen and helium deficient (called Type Ic SNe), broad-lined Type Ic SNe (SNe Ic-bl) are very energetic events, and all SNe coincident with bona fide long duration gamma-ray bursts (LGRBs) are of Type Ic-bl. Understanding the progenitors and the mechanism driving SN Ic-bl explosions vs those of their SNe Ic cousins is key to understanding t… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00872v1-abstract-full').style.display = 'inline'; document.getElementById('1901.00872v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.00872v1-abstract-full" style="display: none;"> Unlike the ordinary supernovae (SNe) some of which are hydrogen and helium deficient (called Type Ic SNe), broad-lined Type Ic SNe (SNe Ic-bl) are very energetic events, and all SNe coincident with bona fide long duration gamma-ray bursts (LGRBs) are of Type Ic-bl. Understanding the progenitors and the mechanism driving SN Ic-bl explosions vs those of their SNe Ic cousins is key to understanding the SN-GRB relationship and jet production in massive stars. Here we present the largest set of host-galaxy spectra of 28 SNe Ic and 14 SN Ic-bl, all discovered before 2013 by the same untargeted survey, namely the Palomar Transient Factory (PTF). We carefully measure their gas-phase metallicities, stellar masses (M*s) and star-formation rates (SFRs) by taking into account recent progress in the metallicity field and propagating uncertainties correctly. We further re-analyze the hosts of 10 literature SN-GRBs using the same methods and compare them to our PTF SN hosts with the goal of constraining their progenitors from their local environments by conducting a thorough statistical comparison, including upper limits. We find that the metallicities, SFRs and M*s of our PTF SN Ic-bl hosts are statistically comparable to those of SN-GRBs, but significantly lower than those of the PTF SNe Ic. The mass-metallicity relations as defined by the SNe Ic-bl and SN-GRBs are not significantly different from the same relations as defined by the SDSS galaxies, in contrast to claims by earlier works. Our findings point towards low metallicity as a crucial ingredient for SN Ic-bl and SN-GRB production since we are able to break the degeneracy between high SFR and low metallicity. We suggest that the PTF SNe Ic-bl may have produced jets that were choked inside the star or were able break out of the star as unseen low-luminosity or off-axis GRBs. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00872v1-abstract-full').style.display = 'none'; document.getElementById('1901.00872v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 3 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">47 pages, 8 figures, submitted to ApJ in Nov 2018</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1901.00871">arXiv:1901.00871</a> <span> [<a href="https://arxiv.org/pdf/1901.00871">pdf</a>, <a href="https://arxiv.org/format/1901.00871">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab4a01">10.3847/1538-4357/ab4a01 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The SPIRITS sample of Luminous Infrared Transients: Uncovering Hidden Supernovae and Dusty Stellar Outbursts in Nearby Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bond%2C+H+E">Howard E. Bond</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Johansson%2C+J">Joel Johansson</a>, <a href="/search/astro-ph?searchtype=author&query=Karambelkar%2C+V">Viraj Karambelkar</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R+M">Ryan M. Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Tinyanont%2C+S">Samaporn Tinyanont</a>, <a href="/search/astro-ph?searchtype=author&query=Ryder%2C+S+D">Stuart D. Ryder</a>, <a href="/search/astro-ph?searchtype=author&query=Cody%2C+A+M">Ann Marie Cody</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Bally%2C+J">John Bally</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Castell%C3%B3n%2C+S">Sergio Castell贸n</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gehrz%2C+R+D">Robert D. Gehrz</a>, <a href="/search/astro-ph?searchtype=author&query=Helou%2C+G">George Helou</a>, <a href="/search/astro-ph?searchtype=author&query=Kilpatrick%2C+C+D">Charles D. Kilpatrick</a>, <a href="/search/astro-ph?searchtype=author&query=Milne%2C+P+A">Peter A. Milne</a>, <a href="/search/astro-ph?searchtype=author&query=Morrell%2C+N">Nidia Morrell</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Phillips%2C+M+M">M. M. Phillips</a>, <a href="/search/astro-ph?searchtype=author&query=Smith%2C+N">Nathan Smith</a>, <a href="/search/astro-ph?searchtype=author&query=van+Dyk%2C+S+D">Schuyler D. van Dyk</a> , et al. (1 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1901.00871v2-abstract-short" style="display: inline;"> We present a systematic study of the most luminous ($M_{\mathrm{IR}}$ [Vega magnitudes] brighter than $-14$) infrared (IR) transients discovered by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) between 2014 and 2018 in nearby galaxies ($D < 35$ Mpc). The sample consists of nine events that span peak IR luminosities of $M_{[4.5],\mathrm{peak}}$ between $-14$ and $-18.2$, show IR colors… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00871v2-abstract-full').style.display = 'inline'; document.getElementById('1901.00871v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1901.00871v2-abstract-full" style="display: none;"> We present a systematic study of the most luminous ($M_{\mathrm{IR}}$ [Vega magnitudes] brighter than $-14$) infrared (IR) transients discovered by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) between 2014 and 2018 in nearby galaxies ($D < 35$ Mpc). The sample consists of nine events that span peak IR luminosities of $M_{[4.5],\mathrm{peak}}$ between $-14$ and $-18.2$, show IR colors between $0.2 < ([3.6]{-}[4.5]) < 3.0$, and fade on timescales between $55$ days $< t_{\mathrm{fade}} < 480$ days. The two reddest events ($A_V > 12$) show multiple, luminous IR outbursts over several years and have directly detected, massive progenitors in archival imaging. With analyses of extensive, multiwavelength follow-up, we suggest the following possible classifications: five obscured core-collapse supernovae (CCSNe), two erupting massive stars, one luminous red nova, and one intermediate-luminosity red transient. We define a control sample of all optically discovered transients recovered in SPIRITS galaxies and satisfying the same selection criteria. The control sample consists of eight CCSNe and one Type Iax SN. We find that 7 of the 13 CCSNe in the SPIRITS sample have lower bounds on their extinction of $2 < A_V < 8$. We estimate a nominal fraction of CCSNe in nearby galaxies that are missed by optical surveys as high as $38.5^{+26.0}_{-21.9}$% (90% confidence). This study suggests that a significant fraction of CCSNe may be heavily obscured by dust and therefore undercounted in the census of nearby CCSNe from optical searches. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1901.00871v2-abstract-full').style.display = 'none'; document.getElementById('1901.00871v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 6 January, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 January, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">47 pages, 16 figures, published in ApJ</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> The Astrophysical Journal 886 (2019) 40 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.07446">arXiv:1809.07446</a> <span> [<a href="https://arxiv.org/pdf/1809.07446">pdf</a>, <a href="https://arxiv.org/format/1809.07446">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/ab04b0">10.3847/1538-4357/ab04b0 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Broad Absorption Line Tidal Disruption Event iPTF15af: Optical and Ultraviolet Evolution </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">I. Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=Bloom%2C+J+S">J. S. Bloom</a>, <a href="/search/astro-ph?searchtype=author&query=Duggan%2C+G">G. Duggan</a>, <a href="/search/astro-ph?searchtype=author&query=Filippenko%2C+A+V">A. V. Filippenko</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Horesh%2C+A">A. Horesh</a>, <a href="/search/astro-ph?searchtype=author&query=Hosseinzadeh%2C+G">G. Hosseinzadeh</a>, <a href="/search/astro-ph?searchtype=author&query=Karamehmetoglu%2C+E">E. Karamehmetoglu</a>, <a href="/search/astro-ph?searchtype=author&query=Levan%2C+A">A. Levan</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Pasham%2C+D+R">D. R. Pasham</a>, <a href="/search/astro-ph?searchtype=author&query=Veilleux%2C+S">S. Veilleux</a>, <a href="/search/astro-ph?searchtype=author&query=Walters%2C+R">R. Walters</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">L. Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Zheng%2C+W">W. Zheng</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1809.07446v2-abstract-short" style="display: inline;"> We present multi-wavelength observations of the tidal disruption event (TDE) iPTF15af, discovered by the intermediate Palomar Transient Factory (iPTF) survey at redshift $z=0.07897$. The optical and ultraviolet (UV) light curves of the transient show a slow decay over five months, in agreement with previous optically discovered TDEs. It also has a comparable black-body peak luminosity of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.07446v2-abstract-full').style.display = 'inline'; document.getElementById('1809.07446v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.07446v2-abstract-full" style="display: none;"> We present multi-wavelength observations of the tidal disruption event (TDE) iPTF15af, discovered by the intermediate Palomar Transient Factory (iPTF) survey at redshift $z=0.07897$. The optical and ultraviolet (UV) light curves of the transient show a slow decay over five months, in agreement with previous optically discovered TDEs. It also has a comparable black-body peak luminosity of $L_{\rm{peak}} \approx 1.5 \times 10^{44}$ erg/s. The inferred temperature from the optical and UV data shows a value of (3$-$5) $\times 10^4$ K. The transient is not detected in X-rays up to $L_X < 3 \times 10^{42}$erg/s within the first five months after discovery. The optical spectra exhibit two distinct broad emission lines in the He II region, and at later times also H$伪$ emission. Additionally, emission from [N III] and [O III] is detected, likely produced by the Bowen fluorescence effect. UV spectra reveal broad emission and absorption lines associated with high-ionization states of N V, C IV, Si IV, and possibly P V. These features, analogous to those of broad absorption line quasars (BAL QSOs), require an absorber with column densities $N_{\rm{H}} > 10^{23}$ cm$^{-2}$. This optically thick gas would also explain the non-detection in soft X-rays. The profile of the absorption lines with the highest column density material at the largest velocity is opposite that of BAL QSOs. We suggest that radiation pressure generated by the TDE flare at early times could have provided the initial acceleration mechanism for this gas. Spectral UV line monitoring of future TDEs could test this proposal. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.07446v2-abstract-full').style.display = 'none'; document.getElementById('1809.07446v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 June, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 19 September, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">20 pages, 12 figures, published in ApJ</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> 2019ApJ...873...92B </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1809.02608">arXiv:1809.02608</a> <span> [<a href="https://arxiv.org/pdf/1809.02608">pdf</a>, <a href="https://arxiv.org/format/1809.02608">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aafe0c">10.3847/1538-4357/aafe0c <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The first tidal disruption flare in ZTF: from photometric selection to multi-wavelength characterization </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=van+Velzen%2C+S">Sjoert van Velzen</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">Suvi Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kara%2C+E">Erin Kara</a>, <a href="/search/astro-ph?searchtype=author&query=Miller-Jones%2C+J+C">James C. Miller-Jones</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">Tiara Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Bright%2C+J">Joe Bright</a>, <a href="/search/astro-ph?searchtype=author&query=Roth%2C+N">Nathaniel Roth</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Huppenkothen%2C+D">Daniela Huppenkothen</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E">Eran Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Frederick%2C+S">Sara Frederick</a>, <a href="/search/astro-ph?searchtype=author&query=Ward%2C+C">Charlotte Ward</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+J">Matthew J. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Fender%2C+R">Rob Fender</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Canella%2C+C">Chris Canella</a>, <a href="/search/astro-ph?searchtype=author&query=Stein%2C+R">Robert Stein</a>, <a href="/search/astro-ph?searchtype=author&query=Giomi%2C+M">Matteo Giomi</a>, <a href="/search/astro-ph?searchtype=author&query=Brinnel%2C+V">Valery Brinnel</a>, <a href="/search/astro-ph?searchtype=author&query=Santen%2C+J">Jakob Santen</a>, <a href="/search/astro-ph?searchtype=author&query=Nordin%2C+J">Jakob Nordin</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E+C">Eric C. Bellm</a> , et al. (15 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1809.02608v2-abstract-short" style="display: inline;"> We present Zwicky Transient Facility (ZTF) observations of the tidal disruption flare AT2018zr/PS18kh reported by Holoien et al. and detected during ZTF commissioning. The ZTF light curve of the tidal disruption event (TDE) samples the rise-to-peak exceptionally well, with 50 days of g- and r-band detections before the time of maximum light. We also present our multi-wavelength follow-up observati… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.02608v2-abstract-full').style.display = 'inline'; document.getElementById('1809.02608v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1809.02608v2-abstract-full" style="display: none;"> We present Zwicky Transient Facility (ZTF) observations of the tidal disruption flare AT2018zr/PS18kh reported by Holoien et al. and detected during ZTF commissioning. The ZTF light curve of the tidal disruption event (TDE) samples the rise-to-peak exceptionally well, with 50 days of g- and r-band detections before the time of maximum light. We also present our multi-wavelength follow-up observations, including the detection of a thermal (kT~100 eV) X-ray source that is two orders of magnitude fainter than the contemporaneous optical/UV blackbody luminosity, and a stringent upper limit to the radio emission. We use observations of 128 known active galactic nuclei (AGN) to assess the quality of the ZTF astrometry, finding a median host-flare distance of 0.2" for genuine nuclear flares. Using ZTF observations of variability from known AGN and supernovae we show how these sources can be separated from TDEs. A combination of light-curve shape, color, and location in the host galaxy can be used to select a clean TDE sample from multi-band optical surveys such as ZTF or LSST. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1809.02608v2-abstract-full').style.display = 'none'; document.getElementById('1809.02608v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 7 September, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">accepted to ApJ, updated with recent Swift data</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.04887">arXiv:1808.04887</a> <span> [<a href="https://arxiv.org/pdf/1808.04887">pdf</a>, <a href="https://arxiv.org/ps/1808.04887">ps</a>, <a href="https://arxiv.org/format/1808.04887">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> </div> <p class="title is-5 mathjax"> A UV Resonance Line Echo from a Shell Around a Hydrogen-Poor Superluminous Supernova </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Fransson%2C+C">C. Fransson</a>, <a href="/search/astro-ph?searchtype=author&query=Vreeswijk%2C+P+M">P. M. Vreeswijk</a>, <a href="/search/astro-ph?searchtype=author&query=Woosley%2C+S+E">S. E. Woosley</a>, <a href="/search/astro-ph?searchtype=author&query=Leloudas%2C+G">G. Leloudas</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">D. A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R+M">R. M. Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B+D">B. D. Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=De+Cia%2C+A">A. De Cia</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D+O">D. O. Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C+U">C. U. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gatkine%2C+P">P. Gatkine</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">A. Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Nyholm%2C+A">A. Nyholm</a>, <a href="/search/astro-ph?searchtype=author&query=Rubin%2C+A">A. Rubin</a>, <a href="/search/astro-ph?searchtype=author&query=Suzuki%2C+N">N. Suzuki</a>, <a href="/search/astro-ph?searchtype=author&query=Wozniak%2C+P">P. Wozniak</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.04887v2-abstract-short" style="display: inline;"> Hydrogen-poor superluminous supernovae (SLSN-I) are a class of rare and energetic explosions discovered in untargeted transient surveys in the past decade. The progenitor stars and the physical mechanism behind their large radiated energies ($\sim10^{51}$ erg) are both debated, with one class of models primarily requiring a large rotational energy, while the other requires very massive progenitors… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.04887v2-abstract-full').style.display = 'inline'; document.getElementById('1808.04887v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.04887v2-abstract-full" style="display: none;"> Hydrogen-poor superluminous supernovae (SLSN-I) are a class of rare and energetic explosions discovered in untargeted transient surveys in the past decade. The progenitor stars and the physical mechanism behind their large radiated energies ($\sim10^{51}$ erg) are both debated, with one class of models primarily requiring a large rotational energy, while the other requires very massive progenitors to either convert kinetic energy into radiation via interaction with circumstellar material (CSM), or engender a pair-instability explosion. Observing the structure of the CSM around SLSN-I offers a powerful test of some scenarios, though direct observations are scarce. Here, we present a series of spectroscopic observations of the SLSN-I iPTF16eh, which reveal both absorption and time- and frequency-variable emission in the Mg II resonance doublet. We show that these observations are naturally explained as a resonance scattering light echo from a circumstellar shell. Modeling the evolution of the emission, we find a shell radius of 0.1 pc and velocity of 3300 km s$^{-1}$, implying the shell was ejected three decades prior to the supernova explosion. These properties match theoretical predictions of pulsational pair-instability shell ejections, and imply the progenitor had a He core mass of $\sim 50-55~{\rm M}_{\odot}$, corresponding to an initial mass of $\sim 115~{\rm M}_{\odot}$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.04887v2-abstract-full').style.display = 'none'; document.getElementById('1808.04887v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 18 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 14 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted. Fixed typo in table header, otherwise unchanged from previous version</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.00969">arXiv:1808.00969</a> <span> [<a href="https://arxiv.org/pdf/1808.00969">pdf</a>, <a href="https://arxiv.org/ps/1808.00969">ps</a>, <a href="https://arxiv.org/format/1808.00969">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/sty3420">10.1093/mnras/sty3420 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Fast, Luminous Ultraviolet Transient AT2018cow: Extreme Supernova, or Disruption of a Star by an Intermediate-Mass Black Hole? </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Mazzali%2C+P+A">Paolo A. Mazzali</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">Suvi Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Taggart%2C+K">Kirsty Taggart</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Mockler%2C+B">Brenna Mockler</a>, <a href="/search/astro-ph?searchtype=author&query=Singh%2C+A">Avinash Singh</a>, <a href="/search/astro-ph?searchtype=author&query=Tominaga%2C+N">Nozomu Tominaga</a>, <a href="/search/astro-ph?searchtype=author&query=Tanaka%2C+M">Masaomi Tanaka</a>, <a href="/search/astro-ph?searchtype=author&query=Watson%2C+A+M">Alan M. Watson</a>, <a href="/search/astro-ph?searchtype=author&query=Ahumada%2C+T">Tom谩s Ahumada</a>, <a href="/search/astro-ph?searchtype=author&query=Anupama%2C+G+C">G. C. Anupama</a>, <a href="/search/astro-ph?searchtype=author&query=Ashall%2C+C">Chris Ashall</a>, <a href="/search/astro-ph?searchtype=author&query=Becerra%2C+R+L">Rosa L. Becerra</a>, <a href="/search/astro-ph?searchtype=author&query=Bersier%2C+D">David Bersier</a>, <a href="/search/astro-ph?searchtype=author&query=Bhalerao%2C+V">Varun Bhalerao</a>, <a href="/search/astro-ph?searchtype=author&query=Bloom%2C+J+S">Joshua S. Bloom</a>, <a href="/search/astro-ph?searchtype=author&query=Butler%2C+N+R">Nathaniel R. Butler</a>, <a href="/search/astro-ph?searchtype=author&query=Copperwheat%2C+C">Chris Copperwheat</a>, <a href="/search/astro-ph?searchtype=author&query=Coughlin%2C+M+W">Michael W. Coughlin</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=Drake%2C+A+J">Andrew J. Drake</a> , et al. (38 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.00969v4-abstract-short" style="display: inline;"> Wide-field optical surveys have begun to uncover large samples of fast (t_rise < 5d), luminous (M_peak < -18), blue transients. While commonly attributed to the breakout of a supernova shock into a dense wind, the great distances to the transients of this class found so far have hampered detailed investigation of their properties. We present photometry and spectroscopy from a comprehensive worldwi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.00969v4-abstract-full').style.display = 'inline'; document.getElementById('1808.00969v4-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.00969v4-abstract-full" style="display: none;"> Wide-field optical surveys have begun to uncover large samples of fast (t_rise < 5d), luminous (M_peak < -18), blue transients. While commonly attributed to the breakout of a supernova shock into a dense wind, the great distances to the transients of this class found so far have hampered detailed investigation of their properties. We present photometry and spectroscopy from a comprehensive worldwide campaign to observe AT2018cow (ATLAS18qqn), the first fast-luminous optical transient to be found in real time at low redshift. Our first spectra (<2 days after discovery) are entirely featureless. A very broad absorption feature suggestive of near-relativistic velocities develops between 3-8 days, then disappears. Broad emission features of H and He develop after >10 days. The spectrum remains extremely hot throughout its evolution, and the photospheric radius contracts with time (receding below R<10^14 cm after 1 month). This behaviour does not match that of any known supernova, although a relativistic jet within a fallback supernova could explain some of the observed features. Alternatively, the transient could originate from the disruption of a star by an intermediate-mass black hole, although this would require long-lasting emission of highly super-Eddington thermal radiation. In either case, AT2018cow suggests that the population of fast luminous transients represents a new class of astrophysical event. Intensive follow-up of this event in its late phases, and of any future events found at comparable distance, will be essential to better constrain their origins. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.00969v4-abstract-full').style.display = 'none'; document.getElementById('1808.00969v4-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 23 November, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Corrected Figure 8 / Table 4 to use final fits. Includes machine-readable photometry table (hopefully for real this time)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1803.00574">arXiv:1803.00574</a> <span> [<a href="https://arxiv.org/pdf/1803.00574">pdf</a>, <a href="https://arxiv.org/format/1803.00574">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aacf8b">10.3847/1538-4357/aacf8b <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> SPIRITS 16tn in NGC 3556: A heavily obscured and low-luminosity supernova at 8.8 Mpc </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">Jacob E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">Mansi M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">Scott M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bond%2C+H+E">Howard E. Bond</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R+M">Ryan M. Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Johansson%2C+J">Joel Johansson</a>, <a href="/search/astro-ph?searchtype=author&query=Horesh%2C+A">Assaf Horesh</a>, <a href="/search/astro-ph?searchtype=author&query=Mooley%2C+K+P">Kunal P. Mooley</a>, <a href="/search/astro-ph?searchtype=author&query=Fender%2C+R">Robert Fender</a>, <a href="/search/astro-ph?searchtype=author&query=De%2C+K">Kishalay De</a>, <a href="/search/astro-ph?searchtype=author&query=O%27Sullivan%2C+D">D贸nal O'Sullivan</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">Frank J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Cody%2C+A+M">Ann Marie Cody</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadia Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Fox%2C+O+D">Ori D. Fox</a>, <a href="/search/astro-ph?searchtype=author&query=Gehrz%2C+R+D">Robert D. Gehrz</a>, <a href="/search/astro-ph?searchtype=author&query=Milne%2C+P+A">Peter A. Milne</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Smith%2C+N">Nathan Smith</a>, <a href="/search/astro-ph?searchtype=author&query=Van+Dyk%2C+S+D">Schuyler D. Van Dyk</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1803.00574v1-abstract-short" style="display: inline;"> We present the discovery by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) of a likely supernova (SN) in NGC 3556 at only 8.8 Mpc, which, despite its proximity, was not detected by optical searches. A luminous infrared (IR) transient at $M_{[4.5]} = -16.7$ mag (Vega), SPIRITS 16tn is coincident with a dust lane in the inclined, star-forming disk of the host. Using IR, optical, and radi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.00574v1-abstract-full').style.display = 'inline'; document.getElementById('1803.00574v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1803.00574v1-abstract-full" style="display: none;"> We present the discovery by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) of a likely supernova (SN) in NGC 3556 at only 8.8 Mpc, which, despite its proximity, was not detected by optical searches. A luminous infrared (IR) transient at $M_{[4.5]} = -16.7$ mag (Vega), SPIRITS 16tn is coincident with a dust lane in the inclined, star-forming disk of the host. Using IR, optical, and radio observations, we attempt to determine the nature of this event. We estimate $A_V \approx$ 8 - 9 mag of extinction, placing it among the three most highly obscured IR-discovered SNe to date. The [4.5] light curve declined at a rate of 0.013 mag day$^{-1}$, and the $[3.6] - [4.5]$ color grew redder from 0.7 to $\gtrsim$ 1.0 mag by 184.7 days post discovery. Optical/IR spectroscopy shows a red continuum, but no clearly discernible features, preventing a definitive spectroscopic classification. Deep radio observations constrain the radio luminosity of SPIRITS 16tn to $L_谓 \lesssim 10^{24}$ erg s$^{-1}$ Hz$^{-1}$ between 3 - 15 GHz, excluding many varieties of radio core-collapse SNe. A type Ia SN is ruled out by the observed red IR color, and lack of features normally attributed to Fe-peak elements in the optical and IR spectra. SPIRITS 16tn was fainter at [4.5] than typical stripped-envelope SNe by $\approx$ 1 mag. Comparison of the spectral energy distribution to SNe II suggests SPIRITS 16tn was both highly obscured, and intrinsically dim, possibly akin to the low-luminosity SN 2005cs. We infer the presence of an IR dust echo powered by a peak luminosity of the transient of $5 \times 10^{40}$ erg s$^{-1} < L_{\mathrm{peak}} < 4\times10^{43}$ erg s$^{-1}$, consistent with the observed range for SNe II. This discovery illustrates the power of IR surveys to overcome the compounding effects of visible extinction and optically sub-luminous events in completing the inventory of nearby SNe. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1803.00574v1-abstract-full').style.display = 'none'; document.getElementById('1803.00574v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 March, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2018. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">25 pages, 10 figures, submitted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1712.04936">arXiv:1712.04936</a> <span> [<a href="https://arxiv.org/pdf/1712.04936">pdf</a>, <a href="https://arxiv.org/format/1712.04936">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4365/aad8b1">10.3847/1538-4365/aad8b1 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Sifting for Sapphires: Systematic Selection of Tidal Disruption Events in iPTF </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">T. Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">S. Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=van+Velzen%2C+S">S. van Velzen</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Leloudas%2C+G">G. Leloudas</a>, <a href="/search/astro-ph?searchtype=author&query=Kong%2C+A+K+H">A. K. H. Kong</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">Russ R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Cao%2C+Y">Y. Cao</a>, <a href="/search/astro-ph?searchtype=author&query=Roy%2C+R">R. Roy</a>, <a href="/search/astro-ph?searchtype=author&query=Petrushevska%2C+T">T. Petrushevska</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1712.04936v2-abstract-short" style="display: inline;"> We present results from a systematic selection of tidal disruption events (TDEs) in a wide-area (4800~deg$^2$), $g+R$ band, Intermediate Palomar Transient Factory (iPTF) experiment. Our selection targets typical optically-selected TDEs: bright ($>$60\% flux increase) and blue transients residing in the center of red galaxies. Using photometric selection criteria to down-select from a total of 493… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1712.04936v2-abstract-full').style.display = 'inline'; document.getElementById('1712.04936v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1712.04936v2-abstract-full" style="display: none;"> We present results from a systematic selection of tidal disruption events (TDEs) in a wide-area (4800~deg$^2$), $g+R$ band, Intermediate Palomar Transient Factory (iPTF) experiment. Our selection targets typical optically-selected TDEs: bright ($>$60\% flux increase) and blue transients residing in the center of red galaxies. Using photometric selection criteria to down-select from a total of 493 nuclear transients to a sample of 26 sources, we then use follow-up UV imaging with the Neil Gehrels Swift Telescope, ground-based optical spectroscopy, and light curve fitting to classify them as 14 Type Ia supernovae (SNe Ia), 9 highly variable active galactic nuclei (AGNs), 2 confirmed TDEs, and 1 potential core-collapse supernova. We find it possible to filter AGNs by employing a more stringent transient color cut ($g-r <$ $-$0.2 mag); further, UV imaging is the best discriminator for filtering SNe, since SNe Ia can appear as blue, optically, as TDEs in their early phases. However, when UV-optical color is unavailable, higher precision astrometry can also effectively reduce SNe contamination in the optical. Our most stringent optical photometric selection criteria yields a 4.5:1 contamination rate, allowing for a manageable number of TDE candidates for complete spectroscopic follow-up and real-time classification in the ZTF era. We measure a TDE per galaxy rate of 1.7$^{+2.9}_{-1.3}$ $\times$10$^{-4}$ gal$^{-1}$ yr$^{-1}$ (90\% CL in Poisson statistics). This does not account for TDEs outside our selection criteria, thus may not reflect the total TDE population, which is yet to be fully mapped. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1712.04936v2-abstract-full').style.display = 'none'; document.getElementById('1712.04936v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 13 August, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 13 December, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">24 pages, 21 figures. Accepted for publication in the Astrophysical Journal Supplement Series</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1711.10501">arXiv:1711.10501</a> <span> [<a href="https://arxiv.org/pdf/1711.10501">pdf</a>, <a href="https://arxiv.org/format/1711.10501">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/aaa356">10.1088/1538-3873/aaa356 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> iPTF Survey for Cool Transients </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">S. M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Amanullah%2C+R">R. Amanullah</a>, <a href="/search/astro-ph?searchtype=author&query=Barlow%2C+T">T. Barlow</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B">B. Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Bulla%2C+M">M. Bulla</a>, <a href="/search/astro-ph?searchtype=author&query=Cao%2C+Y">Y. Cao</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D+O">D. O. Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Ferretti%2C+R">R. Ferretti</a>, <a href="/search/astro-ph?searchtype=author&query=Fox%2C+O+D">O. D. Fox</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">S. Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Goobar%2C+A">A. Goobar</a>, <a href="/search/astro-ph?searchtype=author&query=Ho%2C+A+Y+Q">A. Y. Q. Ho</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">T. Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Karamehmetoglu%2C+E">E. Karamehmetoglu</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">R. R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">A. A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">J. D. Neill</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a> , et al. (3 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1711.10501v2-abstract-short" style="display: inline;"> We performed a wide-area (2000 deg$^{2}$) g and I band experiment as part of a two month extension to the Intermediate Palomar Transient Factory. We discovered 36 extragalactic transients including iPTF17lf, a highly reddened local SN Ia, iPTF17bkj, a new member of the rare class of transitional Ibn/IIn supernovae, and iPTF17be, a candidate luminous blue variable outburst. We do not detect any lum… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.10501v2-abstract-full').style.display = 'inline'; document.getElementById('1711.10501v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1711.10501v2-abstract-full" style="display: none;"> We performed a wide-area (2000 deg$^{2}$) g and I band experiment as part of a two month extension to the Intermediate Palomar Transient Factory. We discovered 36 extragalactic transients including iPTF17lf, a highly reddened local SN Ia, iPTF17bkj, a new member of the rare class of transitional Ibn/IIn supernovae, and iPTF17be, a candidate luminous blue variable outburst. We do not detect any luminous red novae and place an upper limit on their rate. We show that adding a slow-cadence I band component to upcoming surveys such as the Zwicky Transient Facility will improve the photometric selection of cool and dusty transients. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.10501v2-abstract-full').style.display = 'none'; document.getElementById('1711.10501v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 28 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">14 pages, 17 figures. Accepted to PASP</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1711.02671">arXiv:1711.02671</a> <span> [<a href="https://arxiv.org/pdf/1711.02671">pdf</a>, <a href="https://arxiv.org/format/1711.02671">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1038/nature24030">10.1038/nature24030 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Energetic eruptions leading to a peculiar hydrogen-rich explosion of a massive star </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">Iair Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=Howell%2C+D+A">D. Andrew Howell</a>, <a href="/search/astro-ph?searchtype=author&query=Kasen%2C+D">Daniel Kasen</a>, <a href="/search/astro-ph?searchtype=author&query=Bildsten%2C+L">Lars Bildsten</a>, <a href="/search/astro-ph?searchtype=author&query=Hosseinzadeh%2C+G">Griffin Hosseinzadeh</a>, <a href="/search/astro-ph?searchtype=author&query=McCully%2C+C">Curtis McCully</a>, <a href="/search/astro-ph?searchtype=author&query=Wong%2C+Z+C">Zheng Chuen Wong</a>, <a href="/search/astro-ph?searchtype=author&query=Katz%2C+S+R">Sarah Rebekah Katz</a>, <a href="/search/astro-ph?searchtype=author&query=Gal-Yam%2C+A">Avishay Gal-Yam</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">Jesper Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Taddia%2C+F">Francesco Taddia</a>, <a href="/search/astro-ph?searchtype=author&query=Leloudas%2C+G">Giorgos Leloudas</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">Peter E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Horesh%2C+A">Assaf Horesh</a>, <a href="/search/astro-ph?searchtype=author&query=Mooley%2C+K">Kunal Mooley</a>, <a href="/search/astro-ph?searchtype=author&query=Rumsey%2C+C">Clare Rumsey</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. Bradley Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Graham%2C+M+L">Melissa L. Graham</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">Daniel A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Nakar%2C+E">Ehud Nakar</a>, <a href="/search/astro-ph?searchtype=author&query=Shaviv%2C+N+J">Nir J. Shaviv</a>, <a href="/search/astro-ph?searchtype=author&query=Bromberg%2C+O">Omer Bromberg</a>, <a href="/search/astro-ph?searchtype=author&query=Shen%2C+K+J">Ken J. Shen</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E+O">Eran O. Ofek</a> , et al. (28 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1711.02671v1-abstract-short" style="display: inline;"> Every supernova hitherto observed has been considered to be the terminal explosion of a star. Moreover, all supernovae with absorption lines in their spectra show those lines decreasing in velocity over time, as the ejecta expand and thin, revealing slower moving material that was previously hidden. In addition, every supernova that exhibits the absorption lines of hydrogen has one main light-curv… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.02671v1-abstract-full').style.display = 'inline'; document.getElementById('1711.02671v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1711.02671v1-abstract-full" style="display: none;"> Every supernova hitherto observed has been considered to be the terminal explosion of a star. Moreover, all supernovae with absorption lines in their spectra show those lines decreasing in velocity over time, as the ejecta expand and thin, revealing slower moving material that was previously hidden. In addition, every supernova that exhibits the absorption lines of hydrogen has one main light-curve peak, or a plateau in luminosity, lasting approximately 100 days before declining. Here we report observations of iPTF14hls, an event that has spectra identical to a hydrogen-rich core-collapse supernova, but characteristics that differ extensively from those of known supernovae. The light curve has at least five peaks and remains bright for more than 600 days; the absorption lines show little to no decrease in velocity; and the radius of the line-forming region is more than an order of magnitude bigger than the radius of the photosphere derived from the continuum emission. These characteristics are consistent with a shell of several tens of solar masses ejected by the star at supernova-level energies a few hundred days before a terminal explosion. Another possible eruption was recorded at the same position in 1954. Multiple energetic pre-supernova eruptions are expected to occur in stars of 95-130 solar masses, which experience the pulsational pair instability. That model, however, does not account for the continued presence of hydrogen, or the energetics observed here. Another mechanism for the violent ejection of mass in massive stars may be required. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.02671v1-abstract-full').style.display = 'none'; document.getElementById('1711.02671v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 7 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Published in Nature</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1710.07287">arXiv:1710.07287</a> <span> [<a href="https://arxiv.org/pdf/1710.07287">pdf</a>, <a href="https://arxiv.org/format/1710.07287">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aa9522">10.3847/1538-4357/aa9522 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The OmegaWhite survey for short-period variable stars - V. Discovery of an ultracompact hot subdwarf binary with a compact companion in a 44 minute orbit </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Ramsay%2C+G">G. Ramsay</a>, <a href="/search/astro-ph?searchtype=author&query=van+Roestel%2C+J">J. van Roestel</a>, <a href="/search/astro-ph?searchtype=author&query=Brooks%2C+J">J. Brooks</a>, <a href="/search/astro-ph?searchtype=author&query=Macfarlane%2C+S+A">S. A. Macfarlane</a>, <a href="/search/astro-ph?searchtype=author&query=Toma%2C+R">R. Toma</a>, <a href="/search/astro-ph?searchtype=author&query=Groot%2C+P+J">P. J. Groot</a>, <a href="/search/astro-ph?searchtype=author&query=Woudt%2C+P+A">P. A. Woudt</a>, <a href="/search/astro-ph?searchtype=author&query=Bildsten%2C+L">L. Bildsten</a>, <a href="/search/astro-ph?searchtype=author&query=Marsh%2C+T+R">T. R. Marsh</a>, <a href="/search/astro-ph?searchtype=author&query=Green%2C+M+J">M. J. Green</a>, <a href="/search/astro-ph?searchtype=author&query=Breedt%2C+E">E. Breedt</a>, <a href="/search/astro-ph?searchtype=author&query=Kilkenny%2C+D">D. Kilkenny</a>, <a href="/search/astro-ph?searchtype=author&query=Freudenthal%2C+J">J. Freudenthal</a>, <a href="/search/astro-ph?searchtype=author&query=Geier%2C+S">S. Geier</a>, <a href="/search/astro-ph?searchtype=author&query=Heber%2C+U">U. Heber</a>, <a href="/search/astro-ph?searchtype=author&query=Bagnulo%2C+S">S. Bagnulo</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+D+A+H">D. A. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Dhillon%2C+V+S">V. S. Dhillon</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Prince%2C+T+A">T. A. Prince</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1710.07287v1-abstract-short" style="display: inline;"> We report the discovery of the ultracompact hot subdwarf (sdOB) binary OW J074106.0-294811.0 with an orbital period of P$_{\rm orb}=44.66279\pm1.16\times10^{-4}$ min, making it the most compact hot subdwarf binary known. Spectroscopic observations using the VLT, Gemini and Keck telescopes revealed a He-sdOB primary with an intermediate helium abundance, T$_{\rm eff}=39 400\pm500$ K and log(g)=… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.07287v1-abstract-full').style.display = 'inline'; document.getElementById('1710.07287v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1710.07287v1-abstract-full" style="display: none;"> We report the discovery of the ultracompact hot subdwarf (sdOB) binary OW J074106.0-294811.0 with an orbital period of P$_{\rm orb}=44.66279\pm1.16\times10^{-4}$ min, making it the most compact hot subdwarf binary known. Spectroscopic observations using the VLT, Gemini and Keck telescopes revealed a He-sdOB primary with an intermediate helium abundance, T$_{\rm eff}=39 400\pm500$ K and log(g)=$5.74\pm0.09$. High signal-to-noise ratio lightcurves show strong ellipsoidal modulation resulting in a derived sdOB mass $M_{\rm sdOB}=0.23\pm0.12$ M$_\odot$ with a WD companion ($M_{\rm WD}=0.72\pm0.17$ M$_\odot$). The mass ratio was found to be $q = M_{\rm sdOB}/M_{\rm WD}=0.32\pm0.10$. The derived mass for the He-sdOB is inconsistent with the canonical mass for hot sbudwarfs of $\approx0.47$ M$_\odot$. To put constraints on the structure and evolutionary history of the sdOB star we compared the derived T$_{\rm eff}$, log(g) and sdOB mass to evolutionary tracks of helium stars and helium white dwarfs calculated with Modules for Experiments in Stellar Astrophysics (MESA). We find that the best fitting model is a helium white dwarf with a mass of $0.320$ M$_\odot$, which left the common envelope ${\approx}1.1$ Myr ago, is consistent with the observations. As a helium white dwarf with a massive white dwarf companion the object will reach contact in 17.6 Myr at an orbital period of 5 min. Depending on the spin-orbit synchronization timescale the object will either merge to form an R CrB star or end up as a stably accreting AM CVn-type system with a helium white dwarf donor. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.07287v1-abstract-full').style.display = 'none'; document.getElementById('1710.07287v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 19 October, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in ApJ, 13 pages, 7 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1710.05436">arXiv:1710.05436</a> <span> [<a href="https://arxiv.org/pdf/1710.05436">pdf</a>, <a href="https://arxiv.org/format/1710.05436">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="General Relativity and Quantum Cosmology">gr-qc</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1126/science.aap9455">10.1126/science.aap9455 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Illuminating Gravitational Waves: A Concordant Picture of Photons from a Neutron Star Merger </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Nakar%2C+E">E. Nakar</a>, <a href="/search/astro-ph?searchtype=author&query=Singer%2C+L+P">L. P. Singer</a>, <a href="/search/astro-ph?searchtype=author&query=Kaplan%2C+D+L">D. L. Kaplan</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D+O">D. O. Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Van+Sistine%2C+A">A. Van Sistine</a>, <a href="/search/astro-ph?searchtype=author&query=Lau%2C+R+M">R. M. Lau</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Gottlieb%2C+O">O. Gottlieb</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J+E">J. E. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">S. M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Feindt%2C+U">U. Feindt</a>, <a href="/search/astro-ph?searchtype=author&query=Hotokezaka%2C+K">K. Hotokezaka</a>, <a href="/search/astro-ph?searchtype=author&query=Ghosh%2C+S">S. Ghosh</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">D. A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Yu%2C+P+-">P. -C. Yu</a>, <a href="/search/astro-ph?searchtype=author&query=Piran%2C+T">T. Piran</a>, <a href="/search/astro-ph?searchtype=author&query=Allison%2C+J+R">J. R. Allison</a>, <a href="/search/astro-ph?searchtype=author&query=Anupama%2C+G+C">G. C. Anupama</a>, <a href="/search/astro-ph?searchtype=author&query=Balasubramanian%2C+A">A. Balasubramanian</a>, <a href="/search/astro-ph?searchtype=author&query=Bannister%2C+K+W">K. W Bannister</a>, <a href="/search/astro-ph?searchtype=author&query=Bally%2C+J">J. Bally</a>, <a href="/search/astro-ph?searchtype=author&query=Barnes%2C+J">J. Barnes</a>, <a href="/search/astro-ph?searchtype=author&query=Barway%2C+S">S. Barway</a>, <a href="/search/astro-ph?searchtype=author&query=Bellm%2C+E">E. Bellm</a> , et al. (56 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1710.05436v1-abstract-short" style="display: inline;"> Merging neutron stars offer an exquisite laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart EM170817 to gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic dataset, we demonstrate that merging neutron stars are a long-sought production… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.05436v1-abstract-full').style.display = 'inline'; document.getElementById('1710.05436v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1710.05436v1-abstract-full" style="display: none;"> Merging neutron stars offer an exquisite laboratory for simultaneously studying strong-field gravity and matter in extreme environments. We establish the physical association of an electromagnetic counterpart EM170817 to gravitational waves (GW170817) detected from merging neutron stars. By synthesizing a panchromatic dataset, we demonstrate that merging neutron stars are a long-sought production site forging heavy elements by r-process nucleosynthesis. The weak gamma-rays seen in EM170817 are dissimilar to classical short gamma-ray bursts with ultra-relativistic jets. Instead, we suggest that breakout of a wide-angle, mildly-relativistic cocoon engulfing the jet elegantly explains the low-luminosity gamma-rays, the high-luminosity ultraviolet-optical-infrared and the delayed radio/X-ray emission. We posit that all merging neutron stars may lead to a wide-angle cocoon breakout; sometimes accompanied by a successful jet and sometimes a choked jet. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.05436v1-abstract-full').style.display = 'none'; document.getElementById('1710.05436v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 October, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Science, in press DOI 10.1126/science.aap9455, 83 pages, 3 tables, 16 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1710.02917">arXiv:1710.02917</a> <span> [<a href="https://arxiv.org/pdf/1710.02917">pdf</a>, <a href="https://arxiv.org/format/1710.02917">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1088/1538-3873/aaa53f">10.1088/1538-3873/aaa53f <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The SED Machine: a robotic spectrograph for fast transient classification </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Neill%2C+J+D">James D. Neill</a>, <a href="/search/astro-ph?searchtype=author&query=Walters%2C+R">Richard Walters</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">Shrinivas R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">Christoffer Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Ben-Ami%2C+S">Sagi Ben-Ami</a>, <a href="/search/astro-ph?searchtype=author&query=Dekany%2C+R+G">Richard G. Dekany</a>, <a href="/search/astro-ph?searchtype=author&query=Fucik%2C+J+R">Jason R. Fucik</a>, <a href="/search/astro-ph?searchtype=author&query=Konidaris%2C+N">Nick Konidaris</a>, <a href="/search/astro-ph?searchtype=author&query=Nash%2C+R">Reston Nash</a>, <a href="/search/astro-ph?searchtype=author&query=Ngeow%2C+C">Chow-Choong Ngeow</a>, <a href="/search/astro-ph?searchtype=author&query=Ofek%2C+E+O">Eran O. Ofek</a>, <a href="/search/astro-ph?searchtype=author&query=Sullivan%2C+D+O">Donal O' Sullivan</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R">Robert Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Ritter%2C+A">Andreas Ritter</a>, <a href="/search/astro-ph?searchtype=author&query=Vyhmeister%2C+K+E">Karl E. Vyhmeister</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1710.02917v2-abstract-short" style="display: inline;"> Current time domain facilities are finding several hundreds of transient astronomical events a year. The discovery rate is expected to increase in the future as soon as new surveys such as the Zwicky Transient Facility (ZTF) and the Large Synoptic Sky Survey (LSST) come on line. At the present time, the rate at which transients are classified is approximately one order or magnitude lower than the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.02917v2-abstract-full').style.display = 'inline'; document.getElementById('1710.02917v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1710.02917v2-abstract-full" style="display: none;"> Current time domain facilities are finding several hundreds of transient astronomical events a year. The discovery rate is expected to increase in the future as soon as new surveys such as the Zwicky Transient Facility (ZTF) and the Large Synoptic Sky Survey (LSST) come on line. At the present time, the rate at which transients are classified is approximately one order or magnitude lower than the discovery rate, leading to an increasing "follow-up drought". Existing telescopes with moderate aperture can help address this deficit when equipped with spectrographs optimized for spectral classification. Here, we provide an overview of the design, operations and first results of the Spectral Energy Distribution Machine (SEDM), operating on the Palomar 60-inch telescope (P60). The instrument is optimized for classification and high observing efficiency. It combines a low-resolution (R$\sim$100) integral field unit (IFU) spectrograph with "Rainbow Camera" (RC), a multi-band field acquisition camera which also serves as multi-band (ugri) photometer. The SEDM was commissioned during the operation of the intermediate Palomar Transient Factory (iPTF) and has already proved lived up to its promise. The success of the SEDM demonstrates the value of spectrographs optimized to spectral classification. Introduction of similar spectrographs on existing telescopes will help alleviate the follow-up drought and thereby accelerate the rate of discoveries. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1710.02917v2-abstract-full').style.display = 'none'; document.getElementById('1710.02917v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 11 October, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 8 October, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 20 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1708.07124">arXiv:1708.07124</a> <span> [<a href="https://arxiv.org/pdf/1708.07124">pdf</a>, <a href="https://arxiv.org/format/1708.07124">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aaa01f">10.3847/1538-4357/aaa01f <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Early Observations of the Type Ia Supernova iPTF 16abc: A Case of Interaction with Nearby, Unbound Material and/or Strong Ejecta Mixing </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Miller%2C+A+A">A. A. Miller</a>, <a href="/search/astro-ph?searchtype=author&query=Cao%2C+Y">Y. Cao</a>, <a href="/search/astro-ph?searchtype=author&query=Piro%2C+A+L">A. L. Piro</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Bue%2C+B+D">B. D. Bue</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Dhawan%2C+S">S. Dhawan</a>, <a href="/search/astro-ph?searchtype=author&query=Ferretti%2C+R">R. Ferretti</a>, <a href="/search/astro-ph?searchtype=author&query=Fox%2C+O+D">O. D. Fox</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Goobar%2C+A">A. Goobar</a>, <a href="/search/astro-ph?searchtype=author&query=Howell%2C+D+A">D. A. Howell</a>, <a href="/search/astro-ph?searchtype=author&query=Hosseinzadeh%2C+G">G. Hosseinzadeh</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Laher%2C+R+R">R. R. Laher</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F+J">F. J. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=McCully%2C+C">C. McCully</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Taddia%2C+F">F. Taddia</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1708.07124v2-abstract-short" style="display: inline;"> Early observations of Type Ia supernovae (SNe Ia) provide a unique probe of their progenitor systems and explosion physics. Here we report the intermediate Palomar Transient Factory (iPTF) discovery of an extraordinarily young SN Ia, iPTF 16abc. By fitting a power law to our early light curve, we infer that first light for the SN, that is when the SN could have first been detected by our survey, o… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.07124v2-abstract-full').style.display = 'inline'; document.getElementById('1708.07124v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1708.07124v2-abstract-full" style="display: none;"> Early observations of Type Ia supernovae (SNe Ia) provide a unique probe of their progenitor systems and explosion physics. Here we report the intermediate Palomar Transient Factory (iPTF) discovery of an extraordinarily young SN Ia, iPTF 16abc. By fitting a power law to our early light curve, we infer that first light for the SN, that is when the SN could have first been detected by our survey, occurred only $0.15\pm_{0.07}^{0.15}$ days before our first detection. In the $\sim$24 hr after discovery, iPTF 16abc rose by $\sim$2 mag, featuring a near-linear rise in flux for $\gtrsim$3 days. Early spectra show strong C II absorption, which disappears after $\sim$7 days. Unlike the extensivelyobserved SN Ia SN 2011fe, the $(B-V)_0$ colors of iPTF 16abc are blue and nearly constant in the days after explosion. We show that our early observations of iPTF 16abc cannot be explained by either SN shock breakout and the associated, subsequent cooling or the SN ejecta colliding with a stellar companion. Instead, we argue that the early characteristics of iPTF 16abc, including (i) the rapid, near-linear rise, (ii) the nonevolving blue colors, and (iii) the strong C II absorption, are the result of either ejecta interaction with nearby, unbound material or vigorous mixing of radioactive $^{56}$Ni in the SN ejecta, or a combination of the two. In the next few years, dozens of very young \textit{normal} SNe Ia will be discovered, and observations similar to those presented here will constrain the white dwarf explosion mechanism. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1708.07124v2-abstract-full').style.display = 'none'; document.getElementById('1708.07124v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 May, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 23 August, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">18 pages, 12 figures, accepted by ApJ</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> 2018, ApJ, 852, 100 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.08965">arXiv:1706.08965</a> <span> [<a href="https://arxiv.org/pdf/1706.08965">pdf</a>, <a href="https://arxiv.org/format/1706.08965">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/stx1703">10.1093/mnras/stx1703 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Black hole masses of tidal disruption event host galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Wevers%2C+T">Thomas Wevers</a>, <a href="/search/astro-ph?searchtype=author&query=van+Velzen%2C+S">Sjoert van Velzen</a>, <a href="/search/astro-ph?searchtype=author&query=Jonker%2C+P+G">Peter G. Jonker</a>, <a href="/search/astro-ph?searchtype=author&query=Stone%2C+N+C">Nicholas C. Stone</a>, <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">Tiara Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Onori%2C+F">Francesca Onori</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">Suvi Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">Nadejda Blagorodnova</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1706.08965v1-abstract-short" style="display: inline;"> The mass of the central black hole in a galaxy that hosted a tidal disruption event (TDE) is an important parameter in understanding its energetics and dynamics. We present the first homogeneously measured black hole masses of a complete sample of 12 optically/UV selected TDE host galaxies (down to $g_{host}$$\leq$22 mag and $z$=0.37) in the Northern sky. The mass estimates are based on velocity d… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.08965v1-abstract-full').style.display = 'inline'; document.getElementById('1706.08965v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.08965v1-abstract-full" style="display: none;"> The mass of the central black hole in a galaxy that hosted a tidal disruption event (TDE) is an important parameter in understanding its energetics and dynamics. We present the first homogeneously measured black hole masses of a complete sample of 12 optically/UV selected TDE host galaxies (down to $g_{host}$$\leq$22 mag and $z$=0.37) in the Northern sky. The mass estimates are based on velocity dispersion measurements, performed on late time optical spectroscopic observations. We find black hole masses in the range 3$\times$10$^5$ M$_{\odot}$$\leq$M$_{\rm BH}$$\leq$2$\times$10$^7$ M$_{\odot}$. The TDE host galaxy sample is dominated by low mass black holes ($\sim$10$^6$ M$_{\odot}$), as expected from theoretical predictions. The blackbody peak luminosity of TDEs with M$_{\rm BH}$$\leq$10$^{7.1}$ M$_{\odot}$ is consistent with the Eddington limit of the SMBH, whereas the two TDEs with M$_{\rm BH}$$\geq$10$^{7.1}$ M$_{\odot}$ have peak luminosities below their SMBH Eddington luminosity, in line with the theoretical expectation that the fallback rate for M$_{\rm BH}$$\geq$10$^{7.1}$ M$_{\odot}$ is sub-Eddington. In addition, our observations suggest that TDEs around lower mass black holes evolve faster. These findings corroborate the standard TDE picture in 10$^6$ M$_{\odot}$ black holes. Our results imply an increased tension between observational and theoretical TDE rates. By comparing the blackbody emission radius with theoretical predictions, we conclude that the optical/UV emission is produced in a region consistent with the stream self-intersection radius of shallow encounters, ruling out a compact accretion disk as the direct origin of the blackbody radiation at peak brightness. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.08965v1-abstract-full').style.display = 'none'; document.getElementById('1706.08965v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">16 pages, 9 figures. Submitted to MNRAS; including minor revisions suggested by the referee</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.05018">arXiv:1706.05018</a> <span> [<a href="https://arxiv.org/pdf/1706.05018">pdf</a>, <a href="https://arxiv.org/format/1706.05018">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aa99de">10.3847/1538-4357/aa99de <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> iPTF16asu: A Luminous, Rapidly-Evolving, and High-Velocity Supernova </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Whitesides%2C+L">L. Whitesides</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">D. A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Corsi%2C+A">A. Corsi</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Cao%2C+Y">Y. Cao</a>, <a href="/search/astro-ph?searchtype=author&query=Cook%2C+D+O">D. O. Cook</a>, <a href="/search/astro-ph?searchtype=author&query=Doran%2C+G+B">G. B. Doran</a>, <a href="/search/astro-ph?searchtype=author&query=Frederiks%2C+D+D">D. D. Frederiks</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Hurley%2C+K">K. Hurley</a>, <a href="/search/astro-ph?searchtype=author&query=Karamehmetoglu%2C+E">E. Karamehmetoglu</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Leloudas%2C+G">G. Leloudas</a>, <a href="/search/astro-ph?searchtype=author&query=Masci%2C+F">F. Masci</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Ritter%2C+A">A. Ritter</a>, <a href="/search/astro-ph?searchtype=author&query=Rubin%2C+A">A. Rubin</a>, <a href="/search/astro-ph?searchtype=author&query=Savchenko%2C+V">V. Savchenko</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Svinkin%2C+D+S">D. S. Svinkin</a>, <a href="/search/astro-ph?searchtype=author&query=Taddia%2C+F">F. Taddia</a>, <a href="/search/astro-ph?searchtype=author&query=Vreeswijk%2C+P">P. Vreeswijk</a> , et al. (1 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1706.05018v2-abstract-short" style="display: inline;"> Wide-field surveys are discovering a growing number of rare transients whose physical origin is not yet well understood. Here, we present optical and UV data and analysis of iPTF16asu, a luminous, rapidly-evolving, high velocity, stripped-envelope supernova. With a rest-frame rise-time of just 4 days and a peak absolute magnitude of $M_{\rm g}=-20.4$ mag, the light curve of iPTF16asu is faster and… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.05018v2-abstract-full').style.display = 'inline'; document.getElementById('1706.05018v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.05018v2-abstract-full" style="display: none;"> Wide-field surveys are discovering a growing number of rare transients whose physical origin is not yet well understood. Here, we present optical and UV data and analysis of iPTF16asu, a luminous, rapidly-evolving, high velocity, stripped-envelope supernova. With a rest-frame rise-time of just 4 days and a peak absolute magnitude of $M_{\rm g}=-20.4$ mag, the light curve of iPTF16asu is faster and more luminous than previous rapid transients. The spectra of iPTF16asu show a featureless, blue continuum near peak that develops into a Type Ic-BL spectrum on the decline. We show that while the late-time light curve could plausibly be powered by $^{56}$Ni decay, the early emission requires a different energy source. Non-detections in the X-ray and radio strongly constrain any associated gamma-ray burst to be low-luminosity. We suggest that the early emission may have been powered by either a rapidly spinning-down magnetar, or by shock breakout in an extended envelope of a very energetic explosion. In either scenario a central engine is required, making iPTF16asu an intriguing transition object between superluminous supernovae, Type Ic-BL supernovae, and low-energy gamma-ray bursts. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.05018v2-abstract-full').style.display = 'none'; document.getElementById('1706.05018v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 15 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">ApJ in press; matches published version. Minor changes following referee's comments; conclusions unchanged</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> The Astrophysical Journal, Volume 851, Issue 2, article id. 107, 16 pp. (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.00045">arXiv:1706.00045</a> <span> [<a href="https://arxiv.org/pdf/1706.00045">pdf</a>, <a href="https://arxiv.org/format/1706.00045">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aa85e5">10.3847/1538-4357/aa85e5 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> iPTF17cw: An engine-driven supernova candidate discovered independent of a gamma-ray trigger </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Corsi%2C+A">A. Corsi</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R">R. Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Frail%2C+D+A">D. A. Frail</a>, <a href="/search/astro-ph?searchtype=author&query=Goldstein%2C+A+M">A. M. Goldstein</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Connaughton%2C+V">V. Connaughton</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">D. A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Singer%2C+L+P">L. P. Singer</a>, <a href="/search/astro-ph?searchtype=author&query=Copperwheat%2C+C+M">C. M. Copperwheat</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Piascik%2C+A+S">A. S. Piascik</a>, <a href="/search/astro-ph?searchtype=author&query=Steele%2C+I+A">I. A. Steele</a>, <a href="/search/astro-ph?searchtype=author&query=Taddia%2C+F">F. Taddia</a>, <a href="/search/astro-ph?searchtype=author&query=Vedantham%2C+H">H. Vedantham</a>, <a href="/search/astro-ph?searchtype=author&query=Kutyrev%2C+A">A. Kutyrev</a>, <a href="/search/astro-ph?searchtype=author&query=Palliyaguru%2C+N+T">N. T. Palliyaguru</a>, <a href="/search/astro-ph?searchtype=author&query=Roberts%2C+O">O. Roberts</a>, <a href="/search/astro-ph?searchtype=author&query=Sollerman%2C+J">J. Sollerman</a>, <a href="/search/astro-ph?searchtype=author&query=Troja%2C+E">E. Troja</a>, <a href="/search/astro-ph?searchtype=author&query=Veilleux%2C+S">S. Veilleux</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1706.00045v1-abstract-short" style="display: inline;"> We present the discovery, classification, and radio-to-X-ray follow-up observations of iPTF17cw, a broad-lined (BL) type Ic supernova (SN) discovered by the intermediate Palomar Transient Factory (iPTF). Although unrelated to the gravitational wave trigger, this SN was discovered as a happy by-product of the extensive observational campaign dedicated to the follow-up of Advanced LIGO event GW17010… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.00045v1-abstract-full').style.display = 'inline'; document.getElementById('1706.00045v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.00045v1-abstract-full" style="display: none;"> We present the discovery, classification, and radio-to-X-ray follow-up observations of iPTF17cw, a broad-lined (BL) type Ic supernova (SN) discovered by the intermediate Palomar Transient Factory (iPTF). Although unrelated to the gravitational wave trigger, this SN was discovered as a happy by-product of the extensive observational campaign dedicated to the follow-up of Advanced LIGO event GW170104. The spectroscopic properties and inferred peak bolometric luminosity of iPTF17cw are most similar to the gamma-ray burst (GRB) associated SN 1998bw, while the shape of the r-band light curve is most similar to that of the relativistic SN 2009bb. Karl G. Jansky Very Large Array (VLA) observations of the iPTF17cw field reveal a radio counterpart about 10 times less luminous than SN 1998bw, and with peak radio luminosity comparable to that of SN 2006aj/GRB 060218 and SN 2010bh/GRB 100316D. Our radio observations of iPTF17cw imply a relativistically expanding outflow. However, further late-time observations with the VLA in its most extended configuration are needed to confirm fading of iPTF radio counterpart at all frequencies. X-ray observations carried out with Chandra reveal the presence of an X-ray counterpart with luminosity similar to that of SN 2010bh/GRB 100316D. Searching the Fermi catalog for possible gamma-rays reveals that GRB 161228B is spatially and temporally compatible with iPTF17cw. The similarity to SN 1998bw and SN 2009bb, the radio and X-ray detections, and the potential association with GRB 161228B, all point to iPTF17cw being a new candidate member of the rare sample of optically-discovered engine-driven BL-Ic SNe associated with relativistic ejecta. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.00045v1-abstract-full').style.display = 'none'; document.getElementById('1706.00045v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 31 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">13 pages, 9 figures, submitted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.00024">arXiv:1706.00024</a> <span> [<a href="https://arxiv.org/pdf/1706.00024">pdf</a>, <a href="https://arxiv.org/format/1706.00024">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aa81d2">10.3847/1538-4357/aa81d2 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A tale of two transients: GW170104 and GRB170105A </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bhalerao%2C+V">V. Bhalerao</a>, <a href="/search/astro-ph?searchtype=author&query=Kasliwal%2C+M+M">M. M. Kasliwal</a>, <a href="/search/astro-ph?searchtype=author&query=Bhattacharya%2C+D">D. Bhattacharya</a>, <a href="/search/astro-ph?searchtype=author&query=Corsi%2C+A">A. Corsi</a>, <a href="/search/astro-ph?searchtype=author&query=Aarthy%2C+E">E. Aarthy</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+S+M">S. M. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Cantwell%2C+T">T. Cantwell</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Fender%2C+R">R. Fender</a>, <a href="/search/astro-ph?searchtype=author&query=Frail%2C+D">D. Frail</a>, <a href="/search/astro-ph?searchtype=author&query=Itoh%2C+R">R. Itoh</a>, <a href="/search/astro-ph?searchtype=author&query=Jencson%2C+J">J. Jencson</a>, <a href="/search/astro-ph?searchtype=author&query=Kawai%2C+N">N. Kawai</a>, <a href="/search/astro-ph?searchtype=author&query=Kong%2C+A+K+H">A. K. H. Kong</a>, <a href="/search/astro-ph?searchtype=author&query=Kupfer%2C+T">T. Kupfer</a>, <a href="/search/astro-ph?searchtype=author&query=Kutyrev%2C+A">A. Kutyrev</a>, <a href="/search/astro-ph?searchtype=author&query=Mao%2C+J">J. Mao</a>, <a href="/search/astro-ph?searchtype=author&query=Mate%2C+S">S. Mate</a>, <a href="/search/astro-ph?searchtype=author&query=Mithun%2C+N+P+S">N. P. S. Mithun</a>, <a href="/search/astro-ph?searchtype=author&query=Mooley%2C+K">K. Mooley</a>, <a href="/search/astro-ph?searchtype=author&query=Perley%2C+D+A">D. A. Perley</a>, <a href="/search/astro-ph?searchtype=author&query=Perrott%2C+Y+C">Y. C. Perrott</a>, <a href="/search/astro-ph?searchtype=author&query=Quimby%2C+R+M">R. M. Quimby</a>, <a href="/search/astro-ph?searchtype=author&query=Rao%2C+A+R">A. R. Rao</a> , et al. (8 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1706.00024v2-abstract-short" style="display: inline;"> We present multi-wavelength follow-up campaigns by the AstroSat-CZTI and GROWTH collaborations to search for an electromagnetic counterpart to the gravitational wave event GW170104. At the time of the GW170104 trigger, the AstroSat CZTI field-of-view covered 50.3\% of the sky localization. We do not detect any hard X-ray (>100 keV) signal at this time, and place an upper limit of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.00024v2-abstract-full').style.display = 'inline'; document.getElementById('1706.00024v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.00024v2-abstract-full" style="display: none;"> We present multi-wavelength follow-up campaigns by the AstroSat-CZTI and GROWTH collaborations to search for an electromagnetic counterpart to the gravitational wave event GW170104. At the time of the GW170104 trigger, the AstroSat CZTI field-of-view covered 50.3\% of the sky localization. We do not detect any hard X-ray (>100 keV) signal at this time, and place an upper limit of $\approx 4.5 \times 10^{-7}~{\rm erg~cm}^{-2}{\rm~s}^{-1}$ for a 1\,s timescale. Separately, the ATLAS survey reported a rapidly fading optical source dubbed ATLAS17aeu in the error circle of GW170104. Our panchromatic investigation of ATLAS17aeu shows that it is the afterglow of an unrelated long, soft GRB~170105A, with only a fortuitous spatial coincidence with GW170104. We then discuss the properties of this transient in the context of standard long GRB afterglow models. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.00024v2-abstract-full').style.display = 'none'; document.getElementById('1706.00024v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 21 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 31 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">ApJ accepted - updated to match version, 14 pages, 8 figures, 3 tables</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> LIGO-P1700131 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1705.00688">arXiv:1705.00688</a> <span> [<a href="https://arxiv.org/pdf/1705.00688">pdf</a>, <a href="https://arxiv.org/format/1705.00688">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Solar and Stellar Astrophysics">astro-ph.SR</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1051/0004-6361/201629925">10.1051/0004-6361/201629925 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gaia Data Release 1. Testing the parallaxes with local Cepheids and RR Lyrae stars </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Gaia+Collaboration"> Gaia Collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Clementini%2C+G">G. Clementini</a>, <a href="/search/astro-ph?searchtype=author&query=Eyer%2C+L">L. Eyer</a>, <a href="/search/astro-ph?searchtype=author&query=Ripepi%2C+V">V. Ripepi</a>, <a href="/search/astro-ph?searchtype=author&query=Marconi%2C+M">M. Marconi</a>, <a href="/search/astro-ph?searchtype=author&query=Muraveva%2C+T">T. Muraveva</a>, <a href="/search/astro-ph?searchtype=author&query=Garofalo%2C+A">A. Garofalo</a>, <a href="/search/astro-ph?searchtype=author&query=Sarro%2C+L+M">L. M. Sarro</a>, <a href="/search/astro-ph?searchtype=author&query=Palmer%2C+M">M. Palmer</a>, <a href="/search/astro-ph?searchtype=author&query=Luri%2C+X">X. Luri</a>, <a href="/search/astro-ph?searchtype=author&query=Molinaro%2C+R">R. Molinaro</a>, <a href="/search/astro-ph?searchtype=author&query=Rimoldini%2C+L">L. Rimoldini</a>, <a href="/search/astro-ph?searchtype=author&query=Szabados%2C+L">L. Szabados</a>, <a href="/search/astro-ph?searchtype=author&query=Musella%2C+I">I. Musella</a>, <a href="/search/astro-ph?searchtype=author&query=Anderson%2C+R+I">R. I. Anderson</a>, <a href="/search/astro-ph?searchtype=author&query=Prusti%2C+T">T. Prusti</a>, <a href="/search/astro-ph?searchtype=author&query=de+Bruijne%2C+J+H+J">J. H. J. de Bruijne</a>, <a href="/search/astro-ph?searchtype=author&query=Brown%2C+A+G+A">A. G. A. Brown</a>, <a href="/search/astro-ph?searchtype=author&query=Vallenari%2C+A">A. Vallenari</a>, <a href="/search/astro-ph?searchtype=author&query=Babusiaux%2C+C">C. Babusiaux</a>, <a href="/search/astro-ph?searchtype=author&query=Bailer-Jones%2C+C+A+L">C. A. L. Bailer-Jones</a>, <a href="/search/astro-ph?searchtype=author&query=Bastian%2C+U">U. Bastian</a>, <a href="/search/astro-ph?searchtype=author&query=Biermann%2C+M">M. Biermann</a>, <a href="/search/astro-ph?searchtype=author&query=Evans%2C+D+W">D. W. Evans</a>, <a href="/search/astro-ph?searchtype=author&query=Jansen%2C+F">F. Jansen</a> , et al. (566 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1705.00688v1-abstract-short" style="display: inline;"> Parallaxes for 331 classical Cepheids, 31 Type II Cepheids and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, that involve astrometry collected by… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.00688v1-abstract-full').style.display = 'inline'; document.getElementById('1705.00688v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1705.00688v1-abstract-full" style="display: none;"> Parallaxes for 331 classical Cepheids, 31 Type II Cepheids and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). In order to test these first parallax measurements of the primary standard candles of the cosmological distance ladder, that involve astrometry collected by Gaia during the initial 14 months of science operation, we compared them with literature estimates and derived new period-luminosity ($PL$), period-Wesenheit ($PW$) relations for classical and Type II Cepheids and infrared $PL$, $PL$-metallicity ($PLZ$) and optical luminosity-metallicity ($M_V$-[Fe/H]) relations for the RR Lyrae stars, with zero points based on TGAS. The new relations were computed using multi-band ($V,I,J,K_{\mathrm{s}},W_{1}$) photometry and spectroscopic metal abundances available in the literature, and applying three alternative approaches: (i) by linear least squares fitting the absolute magnitudes inferred from direct transformation of the TGAS parallaxes, (ii) by adopting astrometric-based luminosities, and (iii) using a Bayesian fitting approach. TGAS parallaxes bring a significant added value to the previous Hipparcos estimates. The relations presented in this paper represent first Gaia-calibrated relations and form a "work-in-progress" milestone report in the wait for Gaia-only parallaxes of which a first solution will become available with Gaia's Data Release 2 (DR2) in 2018. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1705.00688v1-abstract-full').style.display = 'none'; document.getElementById('1705.00688v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">29 pages, 25 figures. Accepted for publication by A&A</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 605, A79 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1703.01299">arXiv:1703.01299</a> <span> [<a href="https://arxiv.org/pdf/1703.01299">pdf</a>, <a href="https://arxiv.org/ps/1703.01299">ps</a>, <a href="https://arxiv.org/format/1703.01299">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4357/aa7337">10.3847/1538-4357/aa7337 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Revisiting optical tidal disruption events with iPTF16axa </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Hung%2C+T">T. Hung</a>, <a href="/search/astro-ph?searchtype=author&query=Gezari%2C+S">S. Gezari</a>, <a href="/search/astro-ph?searchtype=author&query=Blagorodnova%2C+N">N. Blagorodnova</a>, <a href="/search/astro-ph?searchtype=author&query=Roth%2C+N">N. Roth</a>, <a href="/search/astro-ph?searchtype=author&query=Cenko%2C+S+B">S. B. Cenko</a>, <a href="/search/astro-ph?searchtype=author&query=Kulkarni%2C+S+R">S. R. Kulkarni</a>, <a href="/search/astro-ph?searchtype=author&query=Horesh%2C+A">A. Horesh</a>, <a href="/search/astro-ph?searchtype=author&query=Arcavi%2C+I">I. Arcavi</a>, <a href="/search/astro-ph?searchtype=author&query=McCully%2C+C">C. McCully</a>, <a href="/search/astro-ph?searchtype=author&query=Yan%2C+L">Lin Yan</a>, <a href="/search/astro-ph?searchtype=author&query=Lunnan%2C+R">R. Lunnan</a>, <a href="/search/astro-ph?searchtype=author&query=Fremling%2C+C">C. Fremling</a>, <a href="/search/astro-ph?searchtype=author&query=Cao%2C+Y">Y. Cao</a>, <a href="/search/astro-ph?searchtype=author&query=Nugent%2C+P+E">P. E. Nugent</a>, <a href="/search/astro-ph?searchtype=author&query=Wozniak%2C+P">P. Wozniak</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1703.01299v2-abstract-short" style="display: inline;"> We report the discovery by the intermediate Palomar Transient Factory (iPTF) of a candidate tidal disruption event (TDE) iPTF16axa at $z=0.108$, and present its broadband photometric and spectroscopic evolution from 3 months of follow-up observations with ground-based telescopes and Swift. The light curve is well fitted with a $t^{-5/3}$ decay, and we constrain the rise-time to peak to be $<$49 re… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1703.01299v2-abstract-full').style.display = 'inline'; document.getElementById('1703.01299v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1703.01299v2-abstract-full" style="display: none;"> We report the discovery by the intermediate Palomar Transient Factory (iPTF) of a candidate tidal disruption event (TDE) iPTF16axa at $z=0.108$, and present its broadband photometric and spectroscopic evolution from 3 months of follow-up observations with ground-based telescopes and Swift. The light curve is well fitted with a $t^{-5/3}$ decay, and we constrain the rise-time to peak to be $<$49 rest-frame days after disruption, which is roughly consistent with the fallback timescale expected for the $\sim 5\times$10$^{6}$ $M_\odot$ black hole inferred from the stellar velocity dispersion of the host galaxy. The UV and optical spectral energy distribution (SED) is well described by a constant blackbody temperature of T$\sim$ 3$\times$10$^4$ K over the monitoring period, with an observed peak luminosity of 1.1$\times$10$^{44}$ erg s$^{-1}$. The optical spectra are characterized by a strong blue continuum and broad HeII and H$伪$ lines characteristic of TDEs. We compare the photometric and spectroscopic signatures of iPTF16axa with 11 TDE candidates in the literature with well-sampled optical light curves. Based on a single-temperature fit to the optical and near-UV photometry, most of these TDE candidates have peak luminosities confined between log(L [erg s$^{-1}$]) = 43.4-44.4, with constant temperatures of a few $\times 10^{4}$ K during their power-law declines, implying blackbody radii on the order of ten times the tidal disruption radius, that decrease monotonically with time. For TDE candidates with hydrogen and helium emission, the high helium-to-hydrogen ratios suggest that the emission arises from high-density gas, where nebular arguments break down. We find no correlation between the peak luminosity and the black hole mass, contrary to the expectations for TDEs to have $\dot{M} \propto M_{\rm BH}^{-1/2}$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1703.01299v2-abstract-full').style.display = 'none'; document.getElementById('1703.01299v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 15 May, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 March, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">17 pages, 16 figures. Accepted for publication in The Astrophysical Journal</span> </p> </li> </ol> <nav class="pagination is-small is-centered breathe-horizontal" role="navigation" aria-label="pagination"> <a href="" class="pagination-previous is-invisible">Previous </a> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=50" class="pagination-next" >Next </a> <ul class="pagination-list"> <li> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=0" class="pagination-link is-current" aria-label="Goto page 1">1 </a> </li> <li> <a href="/search/?searchtype=author&query=Blagorodnova%2C+N&start=50" class="pagination-link " aria-label="Page 2" aria-current="page">2 </a> </li> </ul> </nav> <div class="is-hidden-tablet">  <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 2020-02-24</a>  </span> </div> </div> </main> <footer> <div class="columns is-desktop" role="navigation" aria-label="Secondary">  <div 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