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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/2408.10160">arXiv:2408.10160</a> <span> [<a href="https://arxiv.org/pdf/2408.10160">pdf</a>, <a href="https://arxiv.org/format/2408.10160">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> </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/10.3847/2515-5172/ad6f10">10.3847/2515-5172/ad6f10 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo: Morphologies based on UKIDSS NIR Imaging for 71,052 Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K+L">Karen L. Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Galloway%2C+M">Melanie Galloway</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Read%2C+M">Mike Read</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Willett%2C+K">Kyle Willett</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="2408.10160v1-abstract-short" style="display: inline;"> We present morphological classifications based on Galaxy Zoo analysis of 71,052 galaxies with imaging from the United Kingdom Infrared Telescope Infrared Deep Sky Survey (UKIDSS). Galaxies were selected out of the Galaxy Zoo 2 (GZ2) sample, so also have gri imaging from the Sloan Digital Sky Survey. An identical classification tree, and vote weighting/aggregation was applied to both UKIDSS and GZ2… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.10160v1-abstract-full').style.display = 'inline'; document.getElementById('2408.10160v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2408.10160v1-abstract-full" style="display: none;"> We present morphological classifications based on Galaxy Zoo analysis of 71,052 galaxies with imaging from the United Kingdom Infrared Telescope Infrared Deep Sky Survey (UKIDSS). Galaxies were selected out of the Galaxy Zoo 2 (GZ2) sample, so also have gri imaging from the Sloan Digital Sky Survey. An identical classification tree, and vote weighting/aggregation was applied to both UKIDSS and GZ2 classifications enabling direct comparisons. With this Research Note we provide a public release of the GZ:UKIDSS morphologies and discuss some initial comparisons with GZ2. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.10160v1-abstract-full').style.display = 'none'; document.getElementById('2408.10160v1-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 August, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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">3 pages, 1 figure</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2408.04772">arXiv:2408.04772</a> <span> [<a href="https://arxiv.org/pdf/2408.04772">pdf</a>, <a href="https://arxiv.org/format/2408.04772">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/PSJ/ad6e75">10.3847/PSJ/ad6e75 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Jovian Vortex Hunter: a citizen science project to study Jupiter's vortices </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Sankar%2C+R">Ramanakumar Sankar</a>, <a href="/search/astro-ph?searchtype=author&query=Brueshaber%2C+S">Shawn Brueshaber</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Hansen-Koharcheck%2C+C">Candice Hansen-Koharcheck</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Nesmith%2C+C">Cooper Nesmith</a>, <a href="/search/astro-ph?searchtype=author&query=Orton%2C+G">Glenn Orton</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="2408.04772v1-abstract-short" style="display: inline;"> The Jovian atmosphere contains a wide diversity of vortices, which have a large range of sizes, colors and forms in different dynamical regimes. The formation processes for these vortices is poorly understood, and aside from a few known, long-lived ovals, such as the Great Red Spot, and Oval BA, vortex stability and their temporal evolution are currently largely unknown. In this study, we use Juno… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.04772v1-abstract-full').style.display = 'inline'; document.getElementById('2408.04772v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2408.04772v1-abstract-full" style="display: none;"> The Jovian atmosphere contains a wide diversity of vortices, which have a large range of sizes, colors and forms in different dynamical regimes. The formation processes for these vortices is poorly understood, and aside from a few known, long-lived ovals, such as the Great Red Spot, and Oval BA, vortex stability and their temporal evolution are currently largely unknown. In this study, we use JunoCam data and a citizen-science project on Zooniverse to derive a catalog of vortices, some with repeated observations, through May 2018 to Sep 2021, and analyze their associated properties, such as size, location and color. We find that different colored vortices (binned as white, red, brown and dark), follow vastly different distributions in terms of their sizes and where they are found on the planet. We employ a simplified stability criterion using these vortices as a proxy, to derive a minimum Rossby deformation length for the planet of $\sim1800$ km. We find that this value of $L_d$ is largely constant throughout the atmosphere, and does not have an appreciable meridional gradient. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2408.04772v1-abstract-full').style.display = 'none'; document.getElementById('2408.04772v1-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> 8 August, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 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">21 pages, 30 figures, in press at Planetary Science Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2407.16518">arXiv:2407.16518</a> <span> [<a href="https://arxiv.org/pdf/2407.16518">pdf</a>, <a href="https://arxiv.org/format/2407.16518">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="High Energy Physics - Experiment">hep-ex</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Physics - Phenomenology">hep-ph</span> </div> </div> <p class="title is-5 mathjax"> An indirect search for dark matter with a combined analysis of dwarf spheroidal galaxies from VERITAS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Duerr%2C+A">A. Duerr</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">W. Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C+E">C. E. Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+M+N">M. N. Johnson</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a> , et al. (37 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="2407.16518v2-abstract-short" style="display: inline;"> Understanding the nature and identity of dark matter is a key goal in the physics community. In the case that TeV-scale dark matter particles decay or annihilate into standard model particles, very-high-energy (VHE) gamma rays (greater than 100 GeV) will be present in the final state. The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an imaging atmospheric Cherenkov telescop… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.16518v2-abstract-full').style.display = 'inline'; document.getElementById('2407.16518v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2407.16518v2-abstract-full" style="display: none;"> Understanding the nature and identity of dark matter is a key goal in the physics community. In the case that TeV-scale dark matter particles decay or annihilate into standard model particles, very-high-energy (VHE) gamma rays (greater than 100 GeV) will be present in the final state. The Very Energetic Radiation Imaging Telescope Array System (VERITAS) is an imaging atmospheric Cherenkov telescope array that can indirectly detect VHE gamma rays in an energy range of 100 GeV to > 30 TeV. Dwarf spheroidal galaxies (dSphs) are ideal candidates in the search for dark matter due to their high dark matter content, high mass-to-light ratios, and their low gamma-ray fluxes from astrophysical processes. This study uses a legacy data set of 638 hours collected on 17 dSphs, built over 11 years with an observing strategy optimized according to the dark matter content of the targets. The study addresses a broad dark matter particle mass range, extending from 200 GeV to 30 PeV. In the absence of a detection, we set the upper limits on the dark matter velocity-weighted annihilation cross section. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.16518v2-abstract-full').style.display = 'none'; document.getElementById('2407.16518v2-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 August, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 23 July, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">18 pages, 7 figures, 3 tables, accepted in PRD</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2407.11848">arXiv:2407.11848</a> <span> [<a href="https://arxiv.org/pdf/2407.11848">pdf</a>, <a href="https://arxiv.org/format/2407.11848">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> <p class="title is-5 mathjax"> A multi-wavelength study to decipher the 2017 flare of the blazar OJ 287 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Caldwell%2C+J+P">J. P. Caldwell</a>, <a href="/search/astro-ph?searchtype=author&query=Carini%2C+M">M. Carini</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+J">J. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">G. Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">W. Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C+E">C. E. Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">J. Hoang</a> , et al. (49 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="2407.11848v3-abstract-short" style="display: inline;"> In February 2017, the blazar OJ~287 underwent a period of intense multiwavelength activity. It reached a new historic peak in the soft X-ray (0.3-10 keV) band, as measured by Swift-XRT. This event coincides with a very-high-energy (VHE) $纬$-ray outburst that led VERITAS to detect emission above 100 GeV, with a detection significance of $10蟽$ (from 2016 December 9 to 2017 March 31). The time-averag… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.11848v3-abstract-full').style.display = 'inline'; document.getElementById('2407.11848v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2407.11848v3-abstract-full" style="display: none;"> In February 2017, the blazar OJ~287 underwent a period of intense multiwavelength activity. It reached a new historic peak in the soft X-ray (0.3-10 keV) band, as measured by Swift-XRT. This event coincides with a very-high-energy (VHE) $纬$-ray outburst that led VERITAS to detect emission above 100 GeV, with a detection significance of $10蟽$ (from 2016 December 9 to 2017 March 31). The time-averaged VHE $纬$-ray spectrum was consistent with a soft power law ($螕= -3.81 \pm 0.26$) and an integral flux corresponding to $\sim2.4\%$ that of the Crab Nebula above the same energy. Contemporaneous data from multiple instruments across the electromagnetic spectrum reveal complex flaring behavior, primarily in the soft X-ray and VHE bands. To investigate the possible origin of such an event, our study focuses on three distinct activity states: before, during, and after the February 2017 peak. The spectral energy distributions during these periods suggest the presence of at least two non-thermal emission zones, with the more compact one responsible for the observed flare. Broadband modeling results and observations of a new radio knot in the jet of OJ~287 in 2017 are consistent with a flare originating from a strong recollimation shock outside the radio core. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2407.11848v3-abstract-full').style.display = 'none'; document.getElementById('2407.11848v3-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 August, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 16 July, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">21 pages, 7 figures, accepted for publication in The Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2404.02973">arXiv:2404.02973</a> <span> [<a href="https://arxiv.org/pdf/2404.02973">pdf</a>, <a href="https://arxiv.org/format/2404.02973">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Computer Vision and Pattern Recognition">cs.CV</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"> Scaling Laws for Galaxy Images </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Bowles%2C+M">Micah Bowles</a>, <a href="/search/astro-ph?searchtype=author&query=Scaife%2C+A+M+M">Anna M. M. Scaife</a>, <a href="/search/astro-ph?searchtype=author&query=Makechemu%2C+J+S">Jason Shingirai Makechemu</a>, <a href="/search/astro-ph?searchtype=author&query=Gordon%2C+A+J">Alexander J. Gordon</a>, <a href="/search/astro-ph?searchtype=author&query=Ferguson%2C+A+M+N">Annette M. N. Ferguson</a>, <a href="/search/astro-ph?searchtype=author&query=Mann%2C+R+G">Robert G. Mann</a>, <a href="/search/astro-ph?searchtype=author&query=Pearson%2C+J">James Pearson</a>, <a href="/search/astro-ph?searchtype=author&query=Popp%2C+J+J">J眉rgen J. Popp</a>, <a href="/search/astro-ph?searchtype=author&query=Bovy%2C+J">Jo Bovy</a>, <a href="/search/astro-ph?searchtype=author&query=Speagle%2C+J">Josh Speagle</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=G%C3%A9ron%2C+T">Tobias G茅ron</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C+J">Chris J. Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Mantha%2C+K">Kameswara Mantha</a>, <a href="/search/astro-ph?searchtype=author&query=Mohan%2C+D">Devina Mohan</a>, <a href="/search/astro-ph?searchtype=author&query=O%27Ryan%2C+D">David O'Ryan</a>, <a href="/search/astro-ph?searchtype=author&query=Slijepevic%2C+I+V">Inigo V. Slijepevic</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="2404.02973v1-abstract-short" style="display: inline;"> We present the first systematic investigation of supervised scaling laws outside of an ImageNet-like context - on images of galaxies. We use 840k galaxy images and over 100M annotations by Galaxy Zoo volunteers, comparable in scale to Imagenet-1K. We find that adding annotated galaxy images provides a power law improvement in performance across all architectures and all tasks, while adding trainab… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.02973v1-abstract-full').style.display = 'inline'; document.getElementById('2404.02973v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2404.02973v1-abstract-full" style="display: none;"> We present the first systematic investigation of supervised scaling laws outside of an ImageNet-like context - on images of galaxies. We use 840k galaxy images and over 100M annotations by Galaxy Zoo volunteers, comparable in scale to Imagenet-1K. We find that adding annotated galaxy images provides a power law improvement in performance across all architectures and all tasks, while adding trainable parameters is effective only for some (typically more subjectively challenging) tasks. We then compare the downstream performance of finetuned models pretrained on either ImageNet-12k alone vs. additionally pretrained on our galaxy images. We achieve an average relative error rate reduction of 31% across 5 downstream tasks of scientific interest. Our finetuned models are more label-efficient and, unlike their ImageNet-12k-pretrained equivalents, often achieve linear transfer performance equal to that of end-to-end finetuning. We find relatively modest additional downstream benefits from scaling model size, implying that scaling alone is not sufficient to address our domain gap, and suggest that practitioners with qualitatively different images might benefit more from in-domain adaption followed by targeted downstream labelling. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2404.02973v1-abstract-full').style.display = 'none'; document.getElementById('2404.02973v1-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 April, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 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">10+6 pages, 12 figures. Appendix C2 based on arxiv:2206.11927. Code, demos, documentation at https://github.com/mwalmsley/zoobot</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2312.07774">arXiv:2312.07774</a> <span>  </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"> VERITAS contributions to the 38th International Cosmic Ray Conference </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Duerr%2C+A">A. Duerr</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">W. Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C+E">C. E. Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">J. Hoang</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+Z">Z. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+M+N">M. N. Johnson</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a> , et al. (39 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="2312.07774v1-abstract-short" style="display: inline;"> Compilation of papers presented by the VERITAS Collaboration at the 38th International Cosmic Ray Conference (ICRC), held July 26 through August 3, 2023 in Nagoya, Japan. </span> <span class="abstract-full has-text-grey-dark mathjax" id="2312.07774v1-abstract-full" style="display: none;"> Compilation of papers presented by the VERITAS Collaboration at the 38th International Cosmic Ray Conference (ICRC), held July 26 through August 3, 2023 in Nagoya, Japan. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.07774v1-abstract-full').style.display = 'none'; document.getElementById('2312.07774v1-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 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">html page. ICRC 2023, Nagoya, Japan</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2312.03503">arXiv:2312.03503</a> <span> [<a href="https://arxiv.org/pdf/2312.03503">pdf</a>, <a href="https://arxiv.org/format/2312.03503">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="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> </div> <p class="title is-5 mathjax"> Transfer learning for galaxy feature detection: Finding Giant Star-forming Clumps in low redshift galaxies using Faster R-CNN </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Popp%2C+J">J眉rgen Popp</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Serjeant%2C+S">Stephen Serjeant</a>, <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+D">Dominic Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Mantha%2C+K">Kameswara Mantha</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Dawson%2C+J+M">James M. Dawson</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</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="2312.03503v3-abstract-short" style="display: inline;"> Giant Star-forming Clumps (GSFCs) are areas of intensive star-formation that are commonly observed in high-redshift (z>1) galaxies but their formation and role in galaxy evolution remain unclear. High-resolution observations of low-redshift clumpy galaxy analogues are rare and restricted to a limited set of galaxies but the increasing availability of wide-field galaxy survey data makes the detecti… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.03503v3-abstract-full').style.display = 'inline'; document.getElementById('2312.03503v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2312.03503v3-abstract-full" style="display: none;"> Giant Star-forming Clumps (GSFCs) are areas of intensive star-formation that are commonly observed in high-redshift (z>1) galaxies but their formation and role in galaxy evolution remain unclear. High-resolution observations of low-redshift clumpy galaxy analogues are rare and restricted to a limited set of galaxies but the increasing availability of wide-field galaxy survey data makes the detection of large clumpy galaxy samples increasingly feasible. Deep Learning, and in particular CNNs, have been successfully applied to image classification tasks in astrophysical data analysis. However, one application of DL that remains relatively unexplored is that of automatically identifying and localising specific objects or features in astrophysical imaging data. In this paper we demonstrate the feasibility of using Deep learning-based object detection models to localise GSFCs in astrophysical imaging data. We apply the Faster R-CNN object detection framework (FRCNN) to identify GSFCs in low redshift (z<0.3) galaxies. Unlike other studies, we train different FRCNN models not on simulated images with known labels but on real observational data that was collected by the Sloan Digital Sky Survey Legacy Survey and labelled by volunteers from the citizen science project `Galaxy Zoo: Clump Scout'. The FRCNN model relies on a CNN component as a `backbone' feature extractor. We show that CNNs, that have been pre-trained for image classification using astrophysical images, outperform those that have been pre-trained on terrestrial images. In particular, we compare a domain-specific CNN -`Zoobot' - with a generic classification backbone and find that Zoobot achieves higher detection performance and also requires smaller training data sets to do so. Our final model is capable of producing GSFC detections with a completeness and purity of >=0.8 while only being trained on ~5,000 galaxy images. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.03503v3-abstract-full').style.display = 'none'; document.getElementById('2312.03503v3-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 April, 2024; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 6 December, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">Accepted for publication in RASTI, 22 pages</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2309.14871">arXiv:2309.14871</a> <span> [<a href="https://arxiv.org/pdf/2309.14871">pdf</a>, <a href="https://arxiv.org/format/2309.14871">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/10.1051/0004-6361/202348074">10.1051/0004-6361/202348074 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Solar Jet Hunter: a citizen science initiative to identify coronal jets in EUV data sets </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Musset%2C+S">S. Musset</a>, <a href="/search/astro-ph?searchtype=author&query=Jol%2C+P">P. Jol</a>, <a href="/search/astro-ph?searchtype=author&query=Sankar%2C+R">R. Sankar</a>, <a href="/search/astro-ph?searchtype=author&query=Alnahari%2C+S">S. Alnahari</a>, <a href="/search/astro-ph?searchtype=author&query=Kapsiak%2C+C">C. Kapsiak</a>, <a href="/search/astro-ph?searchtype=author&query=Ostlund%2C+E">E. Ostlund</a>, <a href="/search/astro-ph?searchtype=author&query=Lasko%2C+K">K. Lasko</a>, <a href="/search/astro-ph?searchtype=author&query=Glesener%2C+L">L. Glesener</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Fleishman%2C+G+D">G. D. Fleishman</a>, <a href="/search/astro-ph?searchtype=author&query=Panesar%2C+N+K">N. K. Panesar</a>, <a href="/search/astro-ph?searchtype=author&query=Zhang%2C+Y">Y. Zhang</a>, <a href="/search/astro-ph?searchtype=author&query=Jeunon%2C+M">M. Jeunon</a>, <a href="/search/astro-ph?searchtype=author&query=Hurlburt%2C+N">N. Hurlburt</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="2309.14871v1-abstract-short" style="display: inline;"> Context. Solar coronal jets seen in EUV are ubiquitous on the Sun, have been found in and at the edges of active regions, at the boundaries of coronal holes, and in the quiet Sun. Jets have various shapes, sizes, brightness, velocities and duration in time, which complicates their detection by automated algorithms. So far, solar jets reported in the Heliophysics Event Knowledgebase (HEK) have been… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14871v1-abstract-full').style.display = 'inline'; document.getElementById('2309.14871v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2309.14871v1-abstract-full" style="display: none;"> Context. Solar coronal jets seen in EUV are ubiquitous on the Sun, have been found in and at the edges of active regions, at the boundaries of coronal holes, and in the quiet Sun. Jets have various shapes, sizes, brightness, velocities and duration in time, which complicates their detection by automated algorithms. So far, solar jets reported in the Heliophysics Event Knowledgebase (HEK) have been mostly reported by humans looking for them in the data, with different levels of precision regarding their timing and positions. Aims. We create a catalogue of solar jets observed in EUV at 304 脜 containing precise and consistent information on the jet timing, position and extent. Methods. We designed a citizen science project, "Solar Jet Hunter", on the Zooniverse platform, to analyze EUV observations at 304 脜 from the Solar Dynamic Observatory/Atmospheric Imaging Assembly (SDO/AIA). We created movie strips for regions of the Sun in which jets have been reported in HEK and ask the volunteers to 1) confirm the presence of at least one jet in the data and 2) report the timing, position and extent of the jet. Results. We report here the design of the project and the results obtained after the analysis of data from 2011 to 2016. 365 "coronal jet" events from HEK served as input for the citizen science project, equivalent to more than 120,000 images distributed into 9,689 "movie strips". Classification by the citizen scientists resulted with only 21% of the data containing a jet, and 883 individual jets being identified. Conclusions. We demonstrate how citizen science can enhance the analysis of solar data with the example of Solar Jet Hunter. The catalogue of jets thus created is publicly available and will enable statistical studies of jets and related phenomena. This catalogue will also be used as a training set for machines to learn to recognize jets in further data sets. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14871v1-abstract-full').style.display = 'none'; document.getElementById('2309.14871v1-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, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 688, A127 (2024) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2309.14159">arXiv:2309.14159</a> <span> [<a href="https://arxiv.org/pdf/2309.14159">pdf</a>, <a href="https://arxiv.org/format/2309.14159">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"> Long-term monitoring of the radio-galaxy M87 in gamma-rays: joint analysis of MAGIC, VERITAS and Fermi-LAT data </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Molero%2C+M">M. Molero</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Rosillo%2C+M+N">M. Nievas Rosillo</a>, <a href="/search/astro-ph?searchtype=author&query=Pueschel%2C+E">E. Pueschel</a>, <a href="/search/astro-ph?searchtype=author&query=Ribeiro%2C+D">D. Ribeiro</a>, <a href="/search/astro-ph?searchtype=author&query=Acosta%2C+M+V">M. V谩zquez Acosta</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="2309.14159v1-abstract-short" style="display: inline;"> M87 was discovered in the very-high-energy band (VHE, E > 100 GeV) with HEGRA in 2003, long before its emission was detected in the high-energy band (HE, E > 100 MeV) with Fermi-LAT in 2009, opening the window to a new family of extragalactic sources with tilted jets. After a series of major VHE flares in 2005, 2008, and 2010, which were detected in multiple bands, the source has been found in a l… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14159v1-abstract-full').style.display = 'inline'; document.getElementById('2309.14159v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2309.14159v1-abstract-full" style="display: none;"> M87 was discovered in the very-high-energy band (VHE, E > 100 GeV) with HEGRA in 2003, long before its emission was detected in the high-energy band (HE, E > 100 MeV) with Fermi-LAT in 2009, opening the window to a new family of extragalactic sources with tilted jets. After a series of major VHE flares in 2005, 2008, and 2010, which were detected in multiple bands, the source has been found in a low activity state, interrupted only by comparatively smaller-scale flares. MAGIC and VERITAS, two stereoscopic Cherenkov telescope arrays located at Roque de los Muchachos Observatory (Canary Islands, Spain) and the Fred Lawrence Whipple Observatory (Arizona, US), have monitored M87 continuously and in coordination for more than 10 years. In this work, we present the data for 4 years of MAGIC and VERITAS observations corresponding to 2019, 2020, 2021 and 2022. The resulting light curves are shown in daily and monthly scales where no significant variability is observed. In addition, we show the first joint analysis using combined event data from the two VHE instruments and Fermi-LAT to compute the spectral energy distribution. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.14159v1-abstract-full').style.display = 'none'; document.getElementById('2309.14159v1-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 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2023. </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2309.11425">arXiv:2309.11425</a> <span> [<a href="https://arxiv.org/pdf/2309.11425">pdf</a>, <a href="https://arxiv.org/format/2309.11425">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="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo DESI: Detailed Morphology Measurements for 8.7M Galaxies in the DESI Legacy Imaging Surveys </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=G%C3%A9ron%2C+T">Tobias G茅ron</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Scaife%2C+A+M+M">Anna M. M. Scaife</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K+L">Karen L. Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Dawson%2C+J+M">James M. Dawson</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Garland%2C+I+L">Izzy L. Garland</a>, <a href="/search/astro-ph?searchtype=author&query=Mantha%2C+K">Kameswara Mantha</a>, <a href="/search/astro-ph?searchtype=author&query=O%27Ryan%2C+D">David O'Ryan</a>, <a href="/search/astro-ph?searchtype=author&query=Popp%2C+J">J眉rgen Popp</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Baeten%2C+E+M">Elisabeth M. Baeten</a>, <a href="/search/astro-ph?searchtype=author&query=Macmillan%2C+C">Christine Macmillan</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="2309.11425v1-abstract-short" style="display: inline;"> We present detailed morphology measurements for 8.67 million galaxies in the DESI Legacy Imaging Surveys (DECaLS, MzLS, and BASS, plus DES). These are automated measurements made by deep learning models trained on Galaxy Zoo volunteer votes. Our models typically predict the fraction of volunteers selecting each answer to within 5-10\% for every answer to every GZ question. The models are trained o… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.11425v1-abstract-full').style.display = 'inline'; document.getElementById('2309.11425v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2309.11425v1-abstract-full" style="display: none;"> We present detailed morphology measurements for 8.67 million galaxies in the DESI Legacy Imaging Surveys (DECaLS, MzLS, and BASS, plus DES). These are automated measurements made by deep learning models trained on Galaxy Zoo volunteer votes. Our models typically predict the fraction of volunteers selecting each answer to within 5-10\% for every answer to every GZ question. The models are trained on newly-collected votes for DESI-LS DR8 images as well as historical votes from GZ DECaLS. We also release the newly-collected votes. Extending our morphology measurements outside of the previously-released DECaLS/SDSS intersection increases our sky coverage by a factor of 4 (5,000 to 19,000 deg$^2$) and allows for full overlap with complementary surveys including ALFALFA and MaNGA. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2309.11425v1-abstract-full').style.display = 'none'; document.getElementById('2309.11425v1-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 September, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">20 pages. Accepted at MNRAS. Catalog available via https://zenodo.org/record/7786416. Pretrained models available via https://github.com/mwalmsley/zoobot. Vizier and Astro Data Lab access not yet available. With thanks to the Galaxy Zoo volunteers</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2306.17819">arXiv:2306.17819</a> <span> [<a href="https://arxiv.org/pdf/2306.17819">pdf</a>, <a href="https://arxiv.org/format/2306.17819">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"> Multiwavelength Observations of the Blazar PKS 0735+178 in Spatial and Temporal Coincidence with an Astrophysical Neutrino Candidate IceCube-211208A </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">G. Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">W. Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C+E">C. E. Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">J. Hoang</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a> , et al. (185 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="2306.17819v1-abstract-short" style="display: inline;"> We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2$^\circ$ away from the best-fit position of the IceCube neutrino event IceCube-211208A detected on December 8, 2021. The source was in a high-flux state in the optical, ultraviolet, X-ray, and GeV gamma-ray bands around the time of the neutrino event, exhibiting daily variability in the soft X-ra… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.17819v1-abstract-full').style.display = 'inline'; document.getElementById('2306.17819v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2306.17819v1-abstract-full" style="display: none;"> We report on multiwavelength target-of-opportunity observations of the blazar PKS 0735+178, located 2.2$^\circ$ away from the best-fit position of the IceCube neutrino event IceCube-211208A detected on December 8, 2021. The source was in a high-flux state in the optical, ultraviolet, X-ray, and GeV gamma-ray bands around the time of the neutrino event, exhibiting daily variability in the soft X-ray flux. The X-ray data from Swift-XRT and NuSTAR characterize the transition between the low-energy and high-energy components of the broadband spectral energy distribution (SED), and the gamma-ray data from Fermi -LAT, VERITAS, and H.E.S.S. require a spectral cut-off near 100 GeV. Both X-ray and gamma-ray measurements provide strong constraints on the leptonic and hadronic models. We analytically explore a synchrotron self-Compton model, an external Compton model, and a lepto-hadronic model. Models that are entirely based on internal photon fields face serious difficulties in matching the observed SED. The existence of an external photon field in the source would instead explain the observed gamma-ray spectral cut-off in both leptonic and lepto-hadronic models and allow a proton jet power that marginally agrees with the Eddington limit in the lepto-hadronic model. We show a numerical lepto-hadronic model with external target photons that reproduces the observed SED and is reasonably consistent with the neutrino event despite requiring a high jet power. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.17819v1-abstract-full').style.display = 'none'; document.getElementById('2306.17819v1-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> 30 June, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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">21 pages, 3 figures, 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/2306.17680">arXiv:2306.17680</a> <span> [<a href="https://arxiv.org/pdf/2306.17680">pdf</a>, <a href="https://arxiv.org/format/2306.17680">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/10.3847/1538-3881/ace347">10.3847/1538-3881/ace347 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A VERITAS/Breakthrough Listen Search for Optical Technosignatures </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">Atreya Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C">Colin Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">Avery Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">Priyadarshini Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">Pedro Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">Wystan Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">Aryeh Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">Manel Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">Abraham Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Qi Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J">John Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G">Gregory Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">Amy Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Griffin%2C+S">Sean Griffin</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">William Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">David Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">Olivier Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C">Claire Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">John Hoang</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">Jamie Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T">T. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">Weidong Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">Philip Kaaret</a> , et al. (43 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="2306.17680v1-abstract-short" style="display: inline;"> The Breakthrough Listen Initiative is conducting a program using multiple telescopes around the world to search for "technosignatures": artificial transmitters of extraterrestrial origin from beyond our solar system. The VERITAS Collaboration joined this program in 2018, and provides the capability to search for one particular technosignature: optical pulses of a few nanoseconds duration detectabl… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.17680v1-abstract-full').style.display = 'inline'; document.getElementById('2306.17680v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2306.17680v1-abstract-full" style="display: none;"> The Breakthrough Listen Initiative is conducting a program using multiple telescopes around the world to search for "technosignatures": artificial transmitters of extraterrestrial origin from beyond our solar system. The VERITAS Collaboration joined this program in 2018, and provides the capability to search for one particular technosignature: optical pulses of a few nanoseconds duration detectable over interstellar distances. We report here on the analysis and results of dedicated VERITAS observations of Breakthrough Listen targets conducted in 2019 and 2020 and of archival VERITAS data collected since 2012. Thirty hours of dedicated observations of 136 targets and 249 archival observations of 140 targets were analyzed and did not reveal any signals consistent with a technosignature. The results are used to place limits on the fraction of stars hosting transmitting civilizations. We also discuss the minimum-pulse sensitivity of our observations and present VERITAS observations of CALIOP: a space-based pulsed laser onboard the CALIPSO satellite. The detection of these pulses with VERITAS, using the analysis techniques developed for our technosignature search, allows a test of our analysis efficiency and serves as an important proof-of-principle. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2306.17680v1-abstract-full').style.display = 'none'; document.getElementById('2306.17680v1-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> 30 June, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 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">15 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/2305.02860">arXiv:2305.02860</a> <span> [<a href="https://arxiv.org/pdf/2305.02860">pdf</a>, <a href="https://arxiv.org/format/2305.02860">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/acd2d0">10.3847/1538-4357/acd2d0 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS discovery of very high energy gamma-ray emission from S3 1227+25 and multiwavelength observations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">Atreya Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C">Colin Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">Avery Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">Priyadarshini Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">Wystan Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">Aryeh Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J">Jodi Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A">Alisha Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">Manel Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">Abe Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Qi Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J">John Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G">Gregory Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">Amy Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">Greg Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W">William Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">David Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">Olivier Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hinrichs%2C+C">Claire Hinrichs</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">John Hoang</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">Jamie Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">Weidong Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+M">Madalyn Johnson</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">Philip Kaaret</a> , et al. (46 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="2305.02860v1-abstract-short" style="display: inline;"> We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the detection of a hard-spectrum GeV flare on May 15, 2015 with the Fermi-Large Area Telescope (LAT). A combined five-hour VERITAS exposure on May 16th and May 18th… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.02860v1-abstract-full').style.display = 'inline'; document.getElementById('2305.02860v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.02860v1-abstract-full" style="display: none;"> We report the detection of very high energy gamma-ray emission from the blazar S3 1227+25 (VER J1230+253) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS). VERITAS observations of the source were triggered by the detection of a hard-spectrum GeV flare on May 15, 2015 with the Fermi-Large Area Telescope (LAT). A combined five-hour VERITAS exposure on May 16th and May 18th resulted in a strong 13$蟽$ detection with a differential photon spectral index, $螕$ = 3.8 $\pm$ 0.4, and a flux level at 9% of the Crab Nebula above 120 GeV. This also triggered target of opportunity observations with Swift, optical photometry, polarimetry and radio measurements, also presented in this work, in addition to the VERITAS and Fermi-LAT data. A temporal analysis of the gamma-ray flux during this period finds evidence of a shortest variability timescale of $蟿_{obs}$ = 6.2 $\pm$ 0.9 hours, indicating emission from compact regions within the jet, and the combined gamma-ray spectrum shows no strong evidence of a spectral cut-off. An investigation into correlations between the multiwavelength observations found evidence of optical and gamma-ray correlations, suggesting a single-zone model of emission. Finally, the multiwavelength spectral energy distribution is well described by a simple one-zone leptonic synchrotron self-Compton radiation model. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.02860v1-abstract-full').style.display = 'none'; document.getElementById('2305.02860v1-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> 4 May, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">18 pages, 6 figures. Accepted for publication in the Astrophysical Journal (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/2302.08784">arXiv:2302.08784</a> <span> [<a href="https://arxiv.org/pdf/2302.08784">pdf</a>, <a href="https://arxiv.org/format/2302.08784">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="High Energy Physics - Experiment">hep-ex</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="High Energy Physics - Phenomenology">hep-ph</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/acbc7b">10.3847/1538-4357/acbc7b <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Search for Ultraheavy Dark Matter from Observations of Dwarf Spheroidal Galaxies with VERITAS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Baumgart%2C+M">M. Baumgart</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">G. Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W+F">W. F. Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Hoang%2C+J">J. Hoang</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kherlakian%2C+M">M. Kherlakian</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</a> , et al. (29 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="2302.08784v2-abstract-short" style="display: inline;"> Dark matter is a key piece of the current cosmological scenario, with weakly interacting massive particles (WIMPs) a leading dark matter candidate. WIMPs have not been detected in their conventional parameter space (100 GeV $\lesssim M_蠂 \lesssim$ 100 TeV), a mass range accessible with current Imaging Atmospheric Cherenkov Telescopes. As ultraheavy dark matter (UHDM; $M_蠂 \gtrsim$ 100 TeV) has bee… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.08784v2-abstract-full').style.display = 'inline'; document.getElementById('2302.08784v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2302.08784v2-abstract-full" style="display: none;"> Dark matter is a key piece of the current cosmological scenario, with weakly interacting massive particles (WIMPs) a leading dark matter candidate. WIMPs have not been detected in their conventional parameter space (100 GeV $\lesssim M_蠂 \lesssim$ 100 TeV), a mass range accessible with current Imaging Atmospheric Cherenkov Telescopes. As ultraheavy dark matter (UHDM; $M_蠂 \gtrsim$ 100 TeV) has been suggested as an under-explored alternative to the WIMP paradigm, we search for an indirect dark matter annihilation signal in a higher mass range (up to 30 PeV) with the VERITAS gamma-ray observatory. With 216 hours of observations of four dwarf spheroidal galaxies, we perform an unbinned likelihood analysis. We find no evidence of a $纬$-ray signal from UHDM annihilation above the background fluctuation for any individual dwarf galaxy nor for a joint-fit analysis, and consequently constrain the velocity-weighted annihilation cross section of UHDM for dark matter particle masses between 1 TeV and 30 PeV. We additionally set constraints on the allowed radius of a composite UHDM particle. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.08784v2-abstract-full').style.display = 'none'; document.getElementById('2302.08784v2-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> 24 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 17 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">10 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/2302.06686">arXiv:2302.06686</a> <span> [<a href="https://arxiv.org/pdf/2302.06686">pdf</a>, <a href="https://arxiv.org/format/2302.06686">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/acb7e6">10.3847/1538-4357/acb7e6 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS and Fermi-LAT constraints on the Gamma-ray Emission from Superluminous Supernovae SN2015bn and SN2017egm </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Dwarkadas%2C+V+V">V. V. Dwarkadas</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">G. Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Hanlon%2C+W+F">W. F Hanlon</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kherlakian%2C+M">M. Kherlakian</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</a> , et al. (34 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="2302.06686v1-abstract-short" style="display: inline;"> Superluminous supernovae (SLSNe) are a rare class of stellar explosions with luminosities ~10-100 times greater than ordinary core-collapse supernovae. One popular model to explain the enhanced optical output of hydrogen-poor (Type I) SLSNe invokes energy injection from a rapidly spinning magnetar. A prediction in this case is that high-energy gamma rays, generated in the wind nebula of the magnet… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.06686v1-abstract-full').style.display = 'inline'; document.getElementById('2302.06686v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2302.06686v1-abstract-full" style="display: none;"> Superluminous supernovae (SLSNe) are a rare class of stellar explosions with luminosities ~10-100 times greater than ordinary core-collapse supernovae. One popular model to explain the enhanced optical output of hydrogen-poor (Type I) SLSNe invokes energy injection from a rapidly spinning magnetar. A prediction in this case is that high-energy gamma rays, generated in the wind nebula of the magnetar, could escape through the expanding supernova ejecta at late times (months or more after optical peak). This paper presents a search for gamma-ray emission in the broad energy band from 100 MeV to 30 TeV from two Type I SLSNe, SN2015bn, and SN2017egm, using observations from Fermi-LAT and VERITAS. Although no gamma-ray emission was detected from either source, the derived upper limits approach the putative magnetar's spin-down luminosity. Prospects are explored for detecting very-high-energy (VHE; 100 GeV - 100 TeV) emission from SLSNe-I with existing and planned facilities such as VERITAS and CTA. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2302.06686v1-abstract-full').style.display = 'none'; document.getElementById('2302.06686v1-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 February, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">20 pages, 7 figures, 2 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/2301.04498">arXiv:2301.04498</a> <span> [<a href="https://arxiv.org/pdf/2301.04498">pdf</a>, <a href="https://arxiv.org/ps/2301.04498">ps</a>, <a href="https://arxiv.org/format/2301.04498">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/10.3847/2515-5172/acb147">10.3847/2515-5172/acb147 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VTSCat: The VERITAS Catalog of Gamma-Ray Observations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Acharyya%2C+A">A. Acharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Bangale%2C+P">P. Bangale</a>, <a href="/search/astro-ph?searchtype=author&query=Bartkoske%2C+J+T">J. T. Bartkoske</a>, <a href="/search/astro-ph?searchtype=author&query=Batista%2C+P">P. Batista</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gallagher%2C+G">G. Gallagher</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a> , et al. (64 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="2301.04498v2-abstract-short" style="display: inline;"> The ground-based gamma-ray observatory VERITAS (Very Energetic Radiation Imaging Telescope Array System) is sensitive to photons of astrophysical origin with energies in the range between $\approx 85$ GeV to $\approx 30$ TeV. The instrument consists of four 12-m diameter imaging Cherenkov telescopes operating at the Fred Lawrence Whipple Observatory (FLWO) in southern Arizona. VERITAS started four… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.04498v2-abstract-full').style.display = 'inline'; document.getElementById('2301.04498v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2301.04498v2-abstract-full" style="display: none;"> The ground-based gamma-ray observatory VERITAS (Very Energetic Radiation Imaging Telescope Array System) is sensitive to photons of astrophysical origin with energies in the range between $\approx 85$ GeV to $\approx 30$ TeV. The instrument consists of four 12-m diameter imaging Cherenkov telescopes operating at the Fred Lawrence Whipple Observatory (FLWO) in southern Arizona. VERITAS started four-telescope operations in 2007 and collects about 1100 hours of good-weather data per year. The VERITAS collaboration has published over 100 journal articles since 2008 reporting on gamma-ray observations of a large variety of objects: Galactic sources like supernova remnants, pulsar wind nebulae, and binary systems; extragalactic sources like star forming galaxies, dwarf-spheroidal galaxies, and highly-variable active galactic nuclei. This note presents VTSCat: the catalog of high-level data products from all VERITAS publications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.04498v2-abstract-full').style.display = 'none'; document.getElementById('2301.04498v2-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 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 11 January, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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">Version with corrected author list</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Research Notes of the AAS, Volume 7, Number 1, 2023 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2211.02094">arXiv:2211.02094</a> <span> [<a href="https://arxiv.org/pdf/2211.02094">pdf</a>, <a href="https://arxiv.org/format/2211.02094">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> </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/acd181">10.3847/1538-4357/acd181 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Low Metallicity Galaxies from the Dark Energy Survey </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lin%2C+Y">Yu-Heng Lin</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Skillman%2C+E">Evan Skillman</a>, <a href="/search/astro-ph?searchtype=author&query=Hayes%2C+M">Matthew Hayes</a>, <a href="/search/astro-ph?searchtype=author&query=McQuinn%2C+K+B+W">Kristen B. W. McQuinn</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Chworowsky%2C+K">Katherine Chworowsky</a>, <a href="/search/astro-ph?searchtype=author&query=Clarke%2C+L">Leonardo Clarke</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="2211.02094v2-abstract-short" style="display: inline;"> We present a new selection of 358 blue compact dwarf galaxies (BCDs) from 5,000 square degrees in the Dark Energy Survey (DES), and the spectroscopic follow-up of a subsample of 68 objects. For the subsample of 34 objects with deep spectra, we measure the metallicity via the direct T$_e$ method using the auroral [\oiii]$位$ 4363 emission line. These BCDs have an average oxygen abundance of 12+log(O… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.02094v2-abstract-full').style.display = 'inline'; document.getElementById('2211.02094v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2211.02094v2-abstract-full" style="display: none;"> We present a new selection of 358 blue compact dwarf galaxies (BCDs) from 5,000 square degrees in the Dark Energy Survey (DES), and the spectroscopic follow-up of a subsample of 68 objects. For the subsample of 34 objects with deep spectra, we measure the metallicity via the direct T$_e$ method using the auroral [\oiii]$位$ 4363 emission line. These BCDs have an average oxygen abundance of 12+log(O/H)= 7.8, with stellar masses between 10$^7$ to 10$^8$ M$_\odot$ and specific star formation rates between $\sim$ 10$^{-9}$ to 10$^{-7}$ yr$^{-1}$. We compare the position of our BCDs with the Mass-metallicity (M-Z) and Luminosity-metallicity (L-Z) relation derived from the Local Volume Legacy sample. We find the scatter about the M-Z relation is smaller than the scatter about the L-Z relation. We identify a correlation between the offsets from the M-Z and L-Z relation that we suggest is due to the contribution of metal-poor inflows. Finally, we explore the validity of the mass-metallicity-SFR fundamental plane in the mass range probed by our galaxies. We find that BCDs with stellar masses smaller than $10^{8}$M$_{\odot}$ do not follow the extrapolation of the fundamental plane. This result suggests that mechanisms other than the balance between inflows and outflows may be at play in regulating the position of low mass galaxies in the M-Z-SFR space. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2211.02094v2-abstract-full').style.display = 'none'; document.getElementById('2211.02094v2-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> 14 November, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 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">19 pages, 10 figures, 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/2210.03684">arXiv:2210.03684</a> <span> [<a href="https://arxiv.org/pdf/2210.03684">pdf</a>, <a href="https://arxiv.org/format/2210.03684">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> </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/stac2919">10.1093/mnras/stac2919 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo: Clump Scout -- Design and first application of a two-dimensional aggregation tool for citizen science </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+D">Dominic Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Serjeant%2C+S">Stephen Serjeant</a>, <a href="/search/astro-ph?searchtype=author&query=Krawczyk%2C+C">Coleman Krawczyk</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Mantha%2C+K">Kameswara Mantha</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B+D">Brooke D. Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</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="2210.03684v1-abstract-short" style="display: inline;"> Galaxy Zoo: Clump Scout is a web-based citizen science project designed to identify and spatially locate giant star forming clumps in galaxies that were imaged by the Sloan Digital Sky Survey Legacy Survey. We present a statistically driven software framework that is designed to aggregate two-dimensional annotations of clump locations provided by multiple independent Galaxy Zoo: Clump Scout volunt… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.03684v1-abstract-full').style.display = 'inline'; document.getElementById('2210.03684v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2210.03684v1-abstract-full" style="display: none;"> Galaxy Zoo: Clump Scout is a web-based citizen science project designed to identify and spatially locate giant star forming clumps in galaxies that were imaged by the Sloan Digital Sky Survey Legacy Survey. We present a statistically driven software framework that is designed to aggregate two-dimensional annotations of clump locations provided by multiple independent Galaxy Zoo: Clump Scout volunteers and generate a consensus label that identifies the locations of probable clumps within each galaxy. The statistical model our framework is based on allows us to assign false-positive probabilities to each of the clumps we identify, to estimate the skill levels of each of the volunteers who contribute to Galaxy Zoo: Clump Scout and also to quantitatively assess the reliability of the consensus labels that are derived for each subject. We apply our framework to a dataset containing 3,561,454 two-dimensional points, which constitute 1,739,259 annotations of 85,286 distinct subjects provided by 20,999 volunteers. Using this dataset, we identify 128,100 potential clumps distributed among 44,126 galaxies. This dataset can be used to study the prevalence and demographics of giant star forming clumps in low-redshift galaxies. The code for our aggregation software framework is publicly available at: https://github.com/ou-astrophysics/BoxAggregator <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2210.03684v1-abstract-full').style.display = 'none'; document.getElementById('2210.03684v1-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, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">31 pages, 22 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2209.09785">arXiv:2209.09785</a> <span> [<a href="https://arxiv.org/pdf/2209.09785">pdf</a>, <a href="https://arxiv.org/format/2209.09785">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/stac2686">10.1093/mnras/stac2686 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gamma-ray observations of MAXI J1820+070 during the 2018 outburst </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Abe%2C+H">H. Abe</a>, <a href="/search/astro-ph?searchtype=author&query=Abe%2C+S">S. Abe</a>, <a href="/search/astro-ph?searchtype=author&query=Acciari%2C+V+A">V. A. Acciari</a>, <a href="/search/astro-ph?searchtype=author&query=Aniello%2C+T">T. Aniello</a>, <a href="/search/astro-ph?searchtype=author&query=Ansoldi%2C+S">S. Ansoldi</a>, <a href="/search/astro-ph?searchtype=author&query=Antonelli%2C+L+A">L. A. Antonelli</a>, <a href="/search/astro-ph?searchtype=author&query=Engels%2C+A+A">A. Arbet Engels</a>, <a href="/search/astro-ph?searchtype=author&query=Arcaro%2C+C">C. Arcaro</a>, <a href="/search/astro-ph?searchtype=author&query=Artero%2C+M">M. Artero</a>, <a href="/search/astro-ph?searchtype=author&query=Asano%2C+K">K. Asano</a>, <a href="/search/astro-ph?searchtype=author&query=Baack%2C+D">D. Baack</a>, <a href="/search/astro-ph?searchtype=author&query=Babi%C4%87%2C+A">A. Babi膰</a>, <a href="/search/astro-ph?searchtype=author&query=Baquero%2C+A">A. Baquero</a>, <a href="/search/astro-ph?searchtype=author&query=de+Almeida%2C+U+B">U. Barres de Almeida</a>, <a href="/search/astro-ph?searchtype=author&query=Barrio%2C+J+A">J. A. Barrio</a>, <a href="/search/astro-ph?searchtype=author&query=Batkovi%C4%87%2C+I">I. Batkovi膰</a>, <a href="/search/astro-ph?searchtype=author&query=Baxter%2C+J">J. Baxter</a>, <a href="/search/astro-ph?searchtype=author&query=Gonz%C3%A1lez%2C+J+B">J. Becerra Gonz谩lez</a>, <a href="/search/astro-ph?searchtype=author&query=Bednarek%2C+W">W. Bednarek</a>, <a href="/search/astro-ph?searchtype=author&query=Bernardini%2C+E">E. Bernardini</a>, <a href="/search/astro-ph?searchtype=author&query=Bernardos%2C+M">M. Bernardos</a>, <a href="/search/astro-ph?searchtype=author&query=Berti%2C+A">A. Berti</a>, <a href="/search/astro-ph?searchtype=author&query=Besenrieder%2C+J">J. Besenrieder</a>, <a href="/search/astro-ph?searchtype=author&query=Bhattacharyya%2C+W">W. Bhattacharyya</a>, <a href="/search/astro-ph?searchtype=author&query=Bigongiari%2C+C">C. Bigongiari</a> , et al. (418 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="2209.09785v2-abstract-short" style="display: inline;"> MAXI J1820+070 is a low-mass X-ray binary with a black hole as a compact object. This binary underwent an exceptionally bright X-ray outburst from March to October 2018, showing evidence of a non-thermal particle population through its radio emission during this whole period. The combined results of 59.5 hours of observations of the MAXI J1820+070 outburst with the H.E.S.S., MAGIC and VERITAS expe… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2209.09785v2-abstract-full').style.display = 'inline'; document.getElementById('2209.09785v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2209.09785v2-abstract-full" style="display: none;"> MAXI J1820+070 is a low-mass X-ray binary with a black hole as a compact object. This binary underwent an exceptionally bright X-ray outburst from March to October 2018, showing evidence of a non-thermal particle population through its radio emission during this whole period. The combined results of 59.5 hours of observations of the MAXI J1820+070 outburst with the H.E.S.S., MAGIC and VERITAS experiments at energies above 200 GeV are presented, together with Fermi-LAT data between 0.1 and 500 GeV, and multiwavelength observations from radio to X-rays. Gamma-ray emission is not detected from MAXI J1820+070, but the obtained upper limits and the multiwavelength data allow us to put meaningful constraints on the source properties under reasonable assumptions regarding the non-thermal particle population and the jet synchrotron spectrum. In particular, it is possible to show that, if a high-energy gamma-ray emitting region is present during the hard state of the source, its predicted flux should be at most a factor of 20 below the obtained Fermi-LAT upper limits, and closer to them for magnetic fields significantly below equipartition. During the state transitions, under the plausible assumption that electrons are accelerated up to ~ 500 GeV, the multiwavelength data and the gamma-ray upper limits lead consistently to the conclusion that a potential high-energy and very-high-energy gamma-ray emitting region should be located at a distance from the black hole ranging between 10^11 and 10^13 cm. Similar outbursts from low-mass X-ray binaries might be detectable in the near future with upcoming instruments such as CTA. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2209.09785v2-abstract-full').style.display = 'none'; document.getElementById('2209.09785v2-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 October, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 20 September, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">15 pages, 5 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/2202.01098">arXiv:2202.01098</a> <span> [<a href="https://arxiv.org/pdf/2202.01098">pdf</a>, <a href="https://arxiv.org/format/2202.01098">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> </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/ac517d">10.3847/1538-3881/ac517d <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gems of the Galaxy Zoos -- a Wide-Ranging Hubble Space Telescope Gap-Filler Program </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Keel%2C+W+C">William C. Keel</a>, <a href="/search/astro-ph?searchtype=author&query=Tate%2C+J">Jean Tate</a>, <a href="/search/astro-ph?searchtype=author&query=Wong%2C+O+I">O. Ivy Wong</a>, <a href="/search/astro-ph?searchtype=author&query=Banfield%2C+J+K">Julie K. Banfield</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C+J">Chris J. Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K+L">Karen L. Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B+D">Brooke D. Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Cardamone%2C+C">Carolin Cardamone</a>, <a href="/search/astro-ph?searchtype=author&query=Smethurst%2C+R">Rebecca Smethurst</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Shanahan%2C+J">Jesse Shanahan</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Garland%2C+I+L">Izzy L. Garland</a>, <a href="/search/astro-ph?searchtype=author&query=Hancock%2C+C">Colin Hancock</a>, <a href="/search/astro-ph?searchtype=author&query=O%27Ryan%2C+D">David O'Ryan</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="2202.01098v2-abstract-short" style="display: inline;"> We describe the Gems of the Galaxy Zoos (Zoo Gems) project, a gap-filler project using short windows in the Hubble Space Telescope's schedule. As with previous snapshot programs, targets are taken from a pool based on position; we combine objects selected by volunteers in both the Galaxy Zoo and Radio Galaxy Zoo citizen-science projects. Zoo Gems uses exposures with the Advanced Camera for Surveys… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2202.01098v2-abstract-full').style.display = 'inline'; document.getElementById('2202.01098v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2202.01098v2-abstract-full" style="display: none;"> We describe the Gems of the Galaxy Zoos (Zoo Gems) project, a gap-filler project using short windows in the Hubble Space Telescope's schedule. As with previous snapshot programs, targets are taken from a pool based on position; we combine objects selected by volunteers in both the Galaxy Zoo and Radio Galaxy Zoo citizen-science projects. Zoo Gems uses exposures with the Advanced Camera for Surveys (ACS) to address a broad range of topics in galaxy morphology, interstellar-medium content, host galaxies of active galactic nuclei, and galaxy evolution. Science cases include studying galaxy interactions, backlit dust in galaxies, post-starburst systems, rings and peculiar spiral patterns, outliers from the usual color-morphology relation, Green Pea compact starburst systems, double radio sources with spiral host galaxies, and extended emission-line regions around active galactic nuclei. For many of these science categories, final selection of targets from a larger list used public input via a voting process. Highlights to date include the prevalence of tightly-wound spiral structure in blue, apparently early-type galaxies, a nearly complete Einstein ring from a group lens, redder components at lower surface brightness surrounding compact Green Pea starbursts, and high-probability examples of spiral galaxies hosting large double radio sources. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2202.01098v2-abstract-full').style.display = 'none'; document.getElementById('2202.01098v2-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 February, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 February, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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 the Astronomical Journal. Pro-forma replacement to fix typo in author list</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2201.06581">arXiv:2201.06581</a> <span> [<a href="https://arxiv.org/pdf/2201.06581">pdf</a>, <a href="https://arxiv.org/format/2201.06581">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> </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/ac6512">10.3847/1538-4357/ac6512 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo: Clump Scout: Surveying the Local Universe for Giant Star-forming Clumps </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+D">Dominic Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</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="2201.06581v1-abstract-short" style="display: inline;"> Massive, star-forming clumps are a common feature of high-redshift star-forming galaxies. How they formed, and why they are so rare at low redshift, remains unclear. In this paper we identify the largest yet sample of clumpy galaxies (7,052) at low redshift using data from the citizen science project \textit{Galaxy Zoo: Clump Scout}, in which volunteers classified over 58,000 Sloan Digital Sky Sur… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.06581v1-abstract-full').style.display = 'inline'; document.getElementById('2201.06581v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2201.06581v1-abstract-full" style="display: none;"> Massive, star-forming clumps are a common feature of high-redshift star-forming galaxies. How they formed, and why they are so rare at low redshift, remains unclear. In this paper we identify the largest yet sample of clumpy galaxies (7,052) at low redshift using data from the citizen science project \textit{Galaxy Zoo: Clump Scout}, in which volunteers classified over 58,000 Sloan Digital Sky Survey (SDSS) galaxies spanning redshift $0.02 < z < 0.15$. We apply a robust completeness correction by comparing with simulated clumps identified by the same method. Requiring that the ratio of clump-to-galaxy flux in the SDSS $u$ band be greater than 8\% (similar to clump definitions used by other works), we estimate the fraction of local galaxies hosting at least one clump ($f_{clumpy}$) to be $2.68_{-0.30}^{+0.33}\%$. We also compute the same fraction with a less stringent cut of 3\% ($11.33_{-1.16}^{+0.89}\%$), as the higher number count and lower statistical noise of this fraction permits sharper comparison with future low-redshift clumpy galaxy studies. Our results reveal a sharp decline in $f_{clumpy}$ over $0 < z < 0.5$. The minor merger rate remains roughly constant over the same span, so we suggest that minor mergers are unlikely to be the primary driver of clump formation. Instead, the rate of galaxy turbulence is a better tracer for $f_{clumpy}$ over $0 < z < 1.5$ for galaxies of all masses, which supports the idea that clump formation is primarily driven by violent disk instability for all galaxy populations during this period. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2201.06581v1-abstract-full').style.display = 'none'; document.getElementById('2201.06581v1-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> 17 January, 2022; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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">23 pages, 13 figures, 4 tables, 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/2111.04676">arXiv:2111.04676</a> <span> [<a href="https://arxiv.org/pdf/2111.04676">pdf</a>, <a href="https://arxiv.org/format/2111.04676">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/10.1051/0004-6361/202142275">10.1051/0004-6361/202142275 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The throughput calibration of the VERITAS telescopes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hona%2C+B">B. Hona</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kleiner%2C+T+K">T. K Kleiner</a>, <a href="/search/astro-ph?searchtype=author&query=Kumar%2C+S">S. Kumar</a>, <a href="/search/astro-ph?searchtype=author&query=Lang%2C+M+J">M. J. Lang</a>, <a href="/search/astro-ph?searchtype=author&query=Lundy%2C+M">M. Lundy</a>, <a href="/search/astro-ph?searchtype=author&query=Maier%2C+G">G. Maier</a> , et al. (20 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="2111.04676v2-abstract-short" style="display: inline;"> Context. The response of imaging atmospheric Cherenkov telescopes to incident 纬-ray-initiated showers in the atmosphere changes as the telescopes age due to exposure to light and weather. These aging processes affect the reconstructed energies of the events and 纬-ray fluxes. Aims. This work discusses the implementation of signal calibration methods for the Very Energetic Radiation Imaging Telescop… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2111.04676v2-abstract-full').style.display = 'inline'; document.getElementById('2111.04676v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2111.04676v2-abstract-full" style="display: none;"> Context. The response of imaging atmospheric Cherenkov telescopes to incident 纬-ray-initiated showers in the atmosphere changes as the telescopes age due to exposure to light and weather. These aging processes affect the reconstructed energies of the events and 纬-ray fluxes. Aims. This work discusses the implementation of signal calibration methods for the Very Energetic Radiation Imaging Telescope Array System (VERITAS) to account for changes in the optical throughput and detector performance over time. Methods. The total throughput of a Cherenkov telescope is the product of camera-dependent factors, such as the photomultiplier tube gains and their quantum efficiencies, and the mirror reflectivity and Winston cone response to incoming radiation. This document summarizes different methods to determine how the camera gains and mirror reflectivity have evolved over time and how we can calibrate this changing throughput in reconstruction pipelines for imaging atmospheric Cherenkov telescopes. The implementation is validated against seven years of observations with the VERITAS telescopes of the Crab Nebula, which is a reference object in very-high-energy astronomy. Results. Regular optical throughput monitoring and the corresponding signal calibrations are found to be critical for the reconstruction of extensive air shower images. The proposed implementation is applied as a correction to the signals of the photomultiplier tubes in the telescope simulation to produce fine-tuned instrument response functions. This method is shown to be effective for calibrating the acquired 纬-ray data and for recovering the correct energy of the events and photon fluxes. At the same time, it keeps the computational effort of generating Monte Carlo simulations for instrument response functions affordably low. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2111.04676v2-abstract-full').style.display = 'none'; document.getElementById('2111.04676v2-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 November, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 8 November, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 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">19 pages, 20 figures, 2 tables Received: 22 September 2021 / Accepted: 03 November 2021</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 658, A83 (2022) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2110.13181">arXiv:2110.13181</a> <span> [<a href="https://arxiv.org/pdf/2110.13181">pdf</a>, <a href="https://arxiv.org/format/2110.13181">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/ac32bd">10.3847/1538-4357/ac32bd <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Variability and Spectral Characteristics of Three Flaring Gamma-ray Quasars Observed by VERITAS and Fermi-LAT </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Batshoun%2C+J">J. Batshoun</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Cavins%2C+B">B. Cavins</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Coppi%2C+P">P. Coppi</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Houck%2C+M">M. Houck</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a> , et al. (41 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="2110.13181v1-abstract-short" style="display: inline;"> Flat spectrum radio quasars (FSRQs) are the most luminous blazars at GeV energies, but only rarely emit detectable fluxes of TeV gamma rays, typically during bright GeV flares. We explore the gamma-ray variability and spectral characteristics of three FSRQs that have been observed at GeV and TeV energies by Fermi-LAT and VERITAS, making use of almost 100 hours of VERITAS observations spread over 1… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.13181v1-abstract-full').style.display = 'inline'; document.getElementById('2110.13181v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2110.13181v1-abstract-full" style="display: none;"> Flat spectrum radio quasars (FSRQs) are the most luminous blazars at GeV energies, but only rarely emit detectable fluxes of TeV gamma rays, typically during bright GeV flares. We explore the gamma-ray variability and spectral characteristics of three FSRQs that have been observed at GeV and TeV energies by Fermi-LAT and VERITAS, making use of almost 100 hours of VERITAS observations spread over 10 years: 3C 279, PKS 1222+216, and Ton 599. We explain the GeV flux distributions of the sources in terms of a model derived from a stochastic differential equation describing fluctuations in the magnetic field in the accretion disk, and estimate the timescales of magnetic flux accumulation and stochastic instabilities in their accretion disks. We identify distinct flares using a procedure based on Bayesian blocks and analyze their daily and sub-daily variability and gamma-ray energy spectra. Using observations from VERITAS as well as Fermi, Swift, and the Steward Observatory, we model the broadband spectral energy distributions of PKS 1222+216 and Ton 599 during VHE-detected flares in 2014 and 2017, respectively, strongly constraining the jet Doppler factors and gamma-ray emission region locations during these events. Finally, we place theoretical constraints on the potential production of PeV-scale neutrinos during these VHE flares. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.13181v1-abstract-full').style.display = 'none'; document.getElementById('2110.13181v1-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 October, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">34 pages, 13 figures. Accepted for publication in the Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2110.12735">arXiv:2110.12735</a> <span> [<a href="https://arxiv.org/pdf/2110.12735">pdf</a>, <a href="https://arxiv.org/format/2110.12735">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="Computer Vision and Pattern Recognition">cs.CV</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/stac525">10.1093/mnras/stac525 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Practical Galaxy Morphology Tools from Deep Supervised Representation Learning </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Scaife%2C+A+M+M">Anna M. M. Scaife</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Lochner%2C+M">Michelle Lochner</a>, <a href="/search/astro-ph?searchtype=author&query=Etsebeth%2C+V">Verlon Etsebeth</a>, <a href="/search/astro-ph?searchtype=author&query=G%C3%A9ron%2C+T">Tobias G茅ron</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K+L">Karen L. Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Mantha%2C+K+B">Kameswara Bharadwaj Mantha</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B+D">Brooke D. Simmons</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="2110.12735v2-abstract-short" style="display: inline;"> Astronomers have typically set out to solve supervised machine learning problems by creating their own representations from scratch. We show that deep learning models trained to answer every Galaxy Zoo DECaLS question learn meaningful semantic representations of galaxies that are useful for new tasks on which the models were never trained. We exploit these representations to outperform several rec… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.12735v2-abstract-full').style.display = 'inline'; document.getElementById('2110.12735v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2110.12735v2-abstract-full" style="display: none;"> Astronomers have typically set out to solve supervised machine learning problems by creating their own representations from scratch. We show that deep learning models trained to answer every Galaxy Zoo DECaLS question learn meaningful semantic representations of galaxies that are useful for new tasks on which the models were never trained. We exploit these representations to outperform several recent approaches at practical tasks crucial for investigating large galaxy samples. The first task is identifying galaxies of similar morphology to a query galaxy. Given a single galaxy assigned a free text tag by humans (e.g. "#diffuse"), we can find galaxies matching that tag for most tags. The second task is identifying the most interesting anomalies to a particular researcher. Our approach is 100% accurate at identifying the most interesting 100 anomalies (as judged by Galaxy Zoo 2 volunteers). The third task is adapting a model to solve a new task using only a small number of newly-labelled galaxies. Models fine-tuned from our representation are better able to identify ring galaxies than models fine-tuned from terrestrial images (ImageNet) or trained from scratch. We solve each task with very few new labels; either one (for the similarity search) or several hundred (for anomaly detection or fine-tuning). This challenges the longstanding view that deep supervised methods require new large labelled datasets for practical use in astronomy. To help the community benefit from our pretrained models, we release our fine-tuning code Zoobot. Zoobot is accessible to researchers with no prior experience in deep learning. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.12735v2-abstract-full').style.display = 'none'; document.getElementById('2110.12735v2-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> 8 June, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 25 October, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">20 pages plus appendix. Accepted to MNRAS (open-access DOI below). Code, documentation, pretrained models: https://github.com/mwalmsley/zoobot (PyTorch and TensorFlow)</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> MNRAS Volume 513, Issue 2, June 2022, Pages 1581-1599 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2110.01075">arXiv:2110.01075</a> <span> [<a href="https://arxiv.org/pdf/2110.01075">pdf</a>, <a href="https://arxiv.org/format/2110.01075">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/ac2c6a">10.3847/1538-4357/ac2c6a <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Multi-Wavelength Observation Campaign of the TeV Gamma-Ray Binary HESS J0632+057 with NuSTAR, VERITAS, MDM, and Swift </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Tokayer%2C+Y+M">Y. M. Tokayer</a>, <a href="/search/astro-ph?searchtype=author&query=An%2C+H">H. An</a>, <a href="/search/astro-ph?searchtype=author&query=Halpern%2C+J+P">J. P. Halpern</a>, <a href="/search/astro-ph?searchtype=author&query=Kim%2C+J">J. Kim</a>, <a href="/search/astro-ph?searchtype=author&query=Mori%2C+K">K. Mori</a>, <a href="/search/astro-ph?searchtype=author&query=Hailey%2C+C+J">C. J. Hailey</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hona%2C+B">B. Hona</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a> , et al. (31 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="2110.01075v1-abstract-short" style="display: inline;"> HESS J0632+057 belongs to a rare subclass of binary systems which emits gamma-rays above 100 GeV. It stands out for its distinctive high-energy light curve, which features a sharp ``primary'' peak and broader ``secondary'' peak. We present the results of contemporaneous observations by NuSTAR and VERITAS during the secondary peak between Dec. 2019 and Feb. 2020, when the orbital phase ($蠁$) is bet… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.01075v1-abstract-full').style.display = 'inline'; document.getElementById('2110.01075v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2110.01075v1-abstract-full" style="display: none;"> HESS J0632+057 belongs to a rare subclass of binary systems which emits gamma-rays above 100 GeV. It stands out for its distinctive high-energy light curve, which features a sharp ``primary'' peak and broader ``secondary'' peak. We present the results of contemporaneous observations by NuSTAR and VERITAS during the secondary peak between Dec. 2019 and Feb. 2020, when the orbital phase ($蠁$) is between 0.55 and 0.75. NuSTAR detected X-ray spectral evolution, while VERITAS detected TeV emission. We fit a leptonic wind-collision model to the multi-wavelength spectra data obtained over the four NuSTAR and VERITAS observations, constraining the pulsar spin-down luminosity and the magnetization parameter at the shock. Despite long-term monitoring of the source from Oct. 2019 to Mar. 2020, the MDM observatory did not detect significant variation in H$伪$ and H$尾$ line equivalent widths, an expected signature of Be-disk interaction with the pulsar. Furthermore, fitting folded Swift-XRT light curve data with an intra-binary shock model constrained the orbital parameters, suggesting two orbital phases (at $蠁_D = 0.13$ and 0.37) where the pulsar crosses the Be-disk, as well as phases for the periastron ($蠁_0 = 0.30$) and inferior conjunction ($蠁_{\text{IFC}} = 0.75$). The broad-band X-ray spectra with Swift-XRT and NuSTAR allowed us to measure a higher neutral hydrogen column density at one of the predicted disk-passing phases. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2110.01075v1-abstract-full').style.display = 'none'; document.getElementById('2110.01075v1-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 October, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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, 9 figures, 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/2109.11894">arXiv:2109.11894</a> <span> [<a href="https://arxiv.org/pdf/2109.11894">pdf</a>, <a href="https://arxiv.org/format/2109.11894">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/ac29b7">10.3847/1538-4357/ac29b7 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observation of the gamma-ray binary HESS J0632+057 with the H.E.S.S., MAGIC, and VERITAS telescopes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A. Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G">G. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hona%2C+B">B. Hona</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a> , et al. (387 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="2109.11894v1-abstract-short" style="display: inline;"> The results of gamma-ray observations of the binary system HESS J0632+057 collected during 450 hours over 15 years, between 2004 and 2019, are presented. Data taken with the atmospheric Cherenkov telescopes H.E.S.S., MAGIC, and VERITAS at energies above 350 GeV were used together with observations at X-ray energies obtained with Swift-XRT, Chandra, XMM-Newton, NuSTAR, and Suzaku. Some of these obs… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2109.11894v1-abstract-full').style.display = 'inline'; document.getElementById('2109.11894v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2109.11894v1-abstract-full" style="display: none;"> The results of gamma-ray observations of the binary system HESS J0632+057 collected during 450 hours over 15 years, between 2004 and 2019, are presented. Data taken with the atmospheric Cherenkov telescopes H.E.S.S., MAGIC, and VERITAS at energies above 350 GeV were used together with observations at X-ray energies obtained with Swift-XRT, Chandra, XMM-Newton, NuSTAR, and Suzaku. Some of these observations were accompanied by measurements of the H伪 emission line. A significant detection of the modulation of the VHE gamma-ray fluxes with a period of 316.7+-4.4 days is reported, consistent with the period of 317.3+-0.7 days obtained with a refined analysis of X-ray data. The analysis of data of four orbital cycles with dense observational coverage reveals short timescale variability, with flux-decay timescales of less than 20 days at very high energies. Flux variations observed over the time scale of several years indicate orbit-to-orbit variability. The analysis confirms the previously reported correlation of X-ray and gamma-ray emission from the system at very high significance, but can not find any correlation of optical H伪 parameters with X-ray or gamma-ray energy fluxes in simultaneous observations. The key finding is that the emission of HESS J0632+057 in the X-ray and gamma-ray energy bands is highly variable on different time scales. The ratio of gamma-ray to X-ray flux shows the equality or even dominance of the gamma-ray energy range. This wealth of new data is interpreted taking into account the insufficient knowledge of the ephemeris of the system, and discussed in the context of results reported on other gamma-ray binary systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2109.11894v1-abstract-full').style.display = 'none'; document.getElementById('2109.11894v1-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> 24 September, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">Accepted for publication by The Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2109.05119">arXiv:2109.05119</a> <span>  </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"> VERITAS contributions to the 37th International Cosmic Ray Conference </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A. Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hona%2C+B">B. Hona</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a> , et al. (36 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="2109.05119v1-abstract-short" style="display: inline;"> Compilation of papers presented by the VERITAS Collaboration at the 37th International Cosmic Ray Conference (ICRC), held July 12 through July 23, 2021 (online) in Berlin, Germany. </span> <span class="abstract-full has-text-grey-dark mathjax" id="2109.05119v1-abstract-full" style="display: none;"> Compilation of papers presented by the VERITAS Collaboration at the 37th International Cosmic Ray Conference (ICRC), held July 12 through July 23, 2021 (online) in Berlin, Germany. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2109.05119v1-abstract-full').style.display = 'none'; document.getElementById('2109.05119v1-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> 10 September, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">html page. 2021 ICRC, Berlin, Germany</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2106.01386">arXiv:2106.01386</a> <span> [<a href="https://arxiv.org/pdf/2106.01386">pdf</a>, <a href="https://arxiv.org/format/2106.01386">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/ac0623">10.3847/1538-4357/ac0623 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> An Archival Search for Neutron-Star Mergers in Gravitational Waves and Very-High-Energy Gamma Rays </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A. Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a> , et al. (37 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="2106.01386v1-abstract-short" style="display: inline;"> The recent discovery of electromagnetic signals in coincidence with neutron-star mergers has solidified the importance of multimessenger campaigns in studying the most energetic astrophysical events. Pioneering multimessenger observatories, such as LIGO/Virgo and IceCube, record many candidate signals below the detection significance threshold. These sub-threshold event candidates are promising ta… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.01386v1-abstract-full').style.display = 'inline'; document.getElementById('2106.01386v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2106.01386v1-abstract-full" style="display: none;"> The recent discovery of electromagnetic signals in coincidence with neutron-star mergers has solidified the importance of multimessenger campaigns in studying the most energetic astrophysical events. Pioneering multimessenger observatories, such as LIGO/Virgo and IceCube, record many candidate signals below the detection significance threshold. These sub-threshold event candidates are promising targets for multimessenger studies, as the information provided by them may, when combined with contemporaneous gamma-ray observations, lead to significant detections. Here we describe a new method that uses such candidates to search for transient events using archival very-high-energy gamma-ray data from imaging atmospheric Cherenkov telescopes (IACTs). We demonstrate the application of this method to sub-threshold binary neutron star (BNS) merger candidates identified in Advanced LIGO's first observing run. We identify eight hours of archival VERITAS observations coincident with seven BNS merger candidates and search them for TeV emission. No gamma-ray emission is detected; we calculate upper limits on the integral flux and compare them to a short gamma-ray burst model. We anticipate this search method to serve as a starting point for IACT searches with future LIGO/Virgo data releases as well as in other sub-threshold studies for multimessenger transients, such as IceCube neutrinos. Furthermore, it can be deployed immediately with other current-generation IACTs, and has the potential for real-time use that places minimal burden on experimental operations. Lastly, this method may serve as a pilot for studies with the Cherenkov Telescope Array, which has the potential to observe even larger fields of view in its divergent pointing mode. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2106.01386v1-abstract-full').style.display = 'none'; document.getElementById('2106.01386v1-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> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2105.13911">arXiv:2105.13911</a> <span> [<a href="https://arxiv.org/pdf/2105.13911">pdf</a>, <a href="https://arxiv.org/format/2105.13911">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/ac05b9">10.3847/1538-4357/ac05b9 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A Search for TeV Gamma-ray Emission from Pulsar Tails by VERITAS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">Wystan Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J">James Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A">A Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">Abraham Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Farrell%2C+K+A">K. A. Farrell</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Qi Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J">J Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Foote%2C+G+M">G. M. Foote</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">Amy Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">Alasdair Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">David Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">Tarek Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">Olivier Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">Jamie Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">Weidong Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">Philip Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kargaltsev%2C+O">Oleg Kargaltsev</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M+P">Mary P. Kertzman</a> , et al. (34 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="2105.13911v1-abstract-short" style="display: inline;"> We report on the search for very-high-energy gamma-ray emission from the regions around three nearby supersonic pulsars (PSR B0355+54, PSR J0357+3205 and PSR J1740+1000) that exhibit long X-ray tails. To date there is no clear detection of TeV emission from any pulsar tail that is prominent in X-ray or radio. We provide upper limits on the TeV flux, and luminosity, and also compare these limits wi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.13911v1-abstract-full').style.display = 'inline'; document.getElementById('2105.13911v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2105.13911v1-abstract-full" style="display: none;"> We report on the search for very-high-energy gamma-ray emission from the regions around three nearby supersonic pulsars (PSR B0355+54, PSR J0357+3205 and PSR J1740+1000) that exhibit long X-ray tails. To date there is no clear detection of TeV emission from any pulsar tail that is prominent in X-ray or radio. We provide upper limits on the TeV flux, and luminosity, and also compare these limits with other pulsar wind nebulae detected in X-rays and the tail emission model predictions. We find that at least one of the three tails is likely to be detected in observations that are a factor of 2-3 more sensitive. The analysis presented here also has implications for deriving the properties of pulsar tails, for those pulsars whose tails could be detected in TeV. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2105.13911v1-abstract-full').style.display = 'none'; document.getElementById('2105.13911v1-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 May, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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, 6 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/2104.12735">arXiv:2104.12735</a> <span> [<a href="https://arxiv.org/pdf/2104.12735">pdf</a>, <a href="https://arxiv.org/format/2104.12735">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/abf926">10.3847/1538-4357/abf926 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS Observations of the Galactic Center Region at Multi-TeV Gamma-Ray Energies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Adams%2C+C+B">C. B. Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Capasso%2C+M">M. Capasso</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Jin%2C+W">W. Jin</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a> , et al. (34 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="2104.12735v1-abstract-short" style="display: inline;"> The Galactic Center (GC) region hosts a variety of powerful astronomical sources and rare astrophysical processes that emit a large flux of non-thermal radiation. The inner 375 pc x 600 pc region, called the Central Molecular Zone, is home to the supermassive black hole Sagittarius A*, massive cloud complexes, and particle accelerators such as supernova remnants. We present the results of our impr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.12735v1-abstract-full').style.display = 'inline'; document.getElementById('2104.12735v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2104.12735v1-abstract-full" style="display: none;"> The Galactic Center (GC) region hosts a variety of powerful astronomical sources and rare astrophysical processes that emit a large flux of non-thermal radiation. The inner 375 pc x 600 pc region, called the Central Molecular Zone, is home to the supermassive black hole Sagittarius A*, massive cloud complexes, and particle accelerators such as supernova remnants. We present the results of our improved analysis of the very-high-energy (VHE) gamma-ray emission above 2 TeV from the GC using 125 hours of data taken with the VERITAS imaging-atmospheric Cherenkov telescope between 2010 and 2018. The central source VER J1745-290, consistent with the position of Sagittarius A*, is detected at a significance of 38 standard deviations above the background level $(38蟽)$, and we report its spectrum and light curve. Its differential spectrum is consistent with a power law with exponential cutoff, with a spectral index of $2.12^{+0.22}_{-0.17}$, a flux normalization at 5.3 TeV of $1.27^{+0.22}_{-0.23}\times 10^{-13}$ TeV-1 cm-2 s-1, and cutoff energy of $10.0^{+4.0}_{-2.0}$ TeV. We also present results on the diffuse emission near the GC, obtained by combining data from multiple regions along the GC ridge which yield a cumulative significance of $9.5蟽$. The diffuse GC ridge spectrum is best fit by a power law with a hard index of 2.19 $\pm$ 0.20, showing no evidence of a cutoff up to 40 TeV. This strengthens the evidence for a potential accelerator of PeV cosmic rays being present in the GC. We also provide spectra of the other sources in our field of view with significant detections, composite supernova remnant G0.9+0.1 and HESS J1746-285. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2104.12735v1-abstract-full').style.display = 'none'; document.getElementById('2104.12735v1-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 April, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 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">19 pages, 8 figures, Accepted for publication in Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2102.08414">arXiv:2102.08414</a> <span> [<a href="https://arxiv.org/pdf/2102.08414">pdf</a>, <a href="https://arxiv.org/format/2102.08414">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="Computer Vision and Pattern Recognition">cs.CV</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/stab2093">10.1093/mnras/stab2093 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo DECaLS: Detailed Visual Morphology Measurements from Volunteers and Deep Learning for 314,000 Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Geron%2C+T">Tobias Geron</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Krawczyk%2C+C">Coleman Krawczyk</a>, <a href="/search/astro-ph?searchtype=author&query=Willett%2C+K+W">Kyle W. Willett</a>, <a href="/search/astro-ph?searchtype=author&query=Bamford%2C+S">Steven Bamford</a>, <a href="/search/astro-ph?searchtype=author&query=Kelvin%2C+L+S">Lee S. Kelvin</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Gal%2C+Y">Yarin Gal</a>, <a href="/search/astro-ph?searchtype=author&query=Keel%2C+W">William Keel</a>, <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K+L">Karen L. Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B+D">Brooke D. Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Smethurst%2C+R">Rebecca Smethurst</a>, <a href="/search/astro-ph?searchtype=author&query=Smith%2C+L">Lewis Smith</a>, <a href="/search/astro-ph?searchtype=author&query=Baeten%2C+E+M">Elisabeth M. Baeten</a>, <a href="/search/astro-ph?searchtype=author&query=Macmillan%2C+C">Christine Macmillan</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="2102.08414v2-abstract-short" style="display: inline;"> We present Galaxy Zoo DECaLS: detailed visual morphological classifications for Dark Energy Camera Legacy Survey images of galaxies within the SDSS DR8 footprint. Deeper DECaLS images (r=23.6 vs. r=22.2 from SDSS) reveal spiral arms, weak bars, and tidal features not previously visible in SDSS imaging. To best exploit the greater depth of DECaLS images, volunteers select from a new set of answers… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.08414v2-abstract-full').style.display = 'inline'; document.getElementById('2102.08414v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2102.08414v2-abstract-full" style="display: none;"> We present Galaxy Zoo DECaLS: detailed visual morphological classifications for Dark Energy Camera Legacy Survey images of galaxies within the SDSS DR8 footprint. Deeper DECaLS images (r=23.6 vs. r=22.2 from SDSS) reveal spiral arms, weak bars, and tidal features not previously visible in SDSS imaging. To best exploit the greater depth of DECaLS images, volunteers select from a new set of answers designed to improve our sensitivity to mergers and bars. Galaxy Zoo volunteers provide 7.5 million individual classifications over 314,000 galaxies. 140,000 galaxies receive at least 30 classifications, sufficient to accurately measure detailed morphology like bars, and the remainder receive approximately 5. All classifications are used to train an ensemble of Bayesian convolutional neural networks (a state-of-the-art deep learning method) to predict posteriors for the detailed morphology of all 314,000 galaxies. When measured against confident volunteer classifications, the networks are approximately 99% accurate on every question. Morphology is a fundamental feature of every galaxy; our human and machine classifications are an accurate and detailed resource for understanding how galaxies evolve. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2102.08414v2-abstract-full').style.display = 'none'; document.getElementById('2102.08414v2-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, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 16 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">Accepted by MNRAS July '21. Open access DOI below. Data at https://doi.org/10.5281/zenodo.4196266. Code at https://www.github.com/mwalmsley/zoobot. Docs at https://zoobot.readthedocs.io/. Interactive viewer at https://share.streamlit.io/mwalmsley/galaxy-poster/gz_decals_mike_walmsley.py</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2012.07668">arXiv:2012.07668</a> <span> [<a href="https://arxiv.org/pdf/2012.07668">pdf</a>, <a href="https://arxiv.org/format/2012.07668">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> </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/abf7cc">10.3847/2041-8213/abf7cc <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> An old stellar population or diffuse nebular continuum emission discovered in green pea galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Clarke%2C+L">Leonardo Clarke</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Keel%2C+W+C">William C. Keel</a>, <a href="/search/astro-ph?searchtype=author&query=Cardamone%2C+C">Carolin Cardamone</a>, <a href="/search/astro-ph?searchtype=author&query=Hayes%2C+M">Matthew Hayes</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+N">Nico Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</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="2012.07668v1-abstract-short" style="display: inline;"> We use new HST images of nine Green Pea Galaxies (GPGs) to study their resolved structure and color. The choice of filters, F555W and F850LP, together with the redshift of the galaxies ($z\sim 0.25$), minimizes the contribution of the nebular [O\thinspace{\sc iii}] and H$伪$ emission lines to the broad-band images. While these galaxies are typically very blue in color, our analysis reveals that it… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2012.07668v1-abstract-full').style.display = 'inline'; document.getElementById('2012.07668v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2012.07668v1-abstract-full" style="display: none;"> We use new HST images of nine Green Pea Galaxies (GPGs) to study their resolved structure and color. The choice of filters, F555W and F850LP, together with the redshift of the galaxies ($z\sim 0.25$), minimizes the contribution of the nebular [O\thinspace{\sc iii}] and H$伪$ emission lines to the broad-band images. While these galaxies are typically very blue in color, our analysis reveals that it is only the dominant stellar clusters that are blue. Each GPG does clearly show the presence of at least one bright and compact star-forming region, but these are invariably superimposed on a more extended and lower surface brightness emission. Moreover, the colors of the star forming regions are on average bluer than those of the diffuse emission, reaching up to 0.6 magnitudes bluer. Assuming that the diffuse and compact components have constant and single burst Star Formation Histories, respectively, the observed colors imply that the diffuse components (possibly the host galaxy of the star-formation episode) have, on average, old stellar ages ($>1$Gyr), while the star-clusters are younger than 500Myrs. We also discuss the possibility that the diffuse red emission is due to a varying relative contribution of nebular continuum, rather than a different stellar population. With the available data, however, it is not possible to distinguish between these two interpretations. A substantial presence of old stars would indicate that the mechanisms that allow large escape fractions in these local galaxies may be different from those at play during the reionization epoch. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2012.07668v1-abstract-full').style.display = 'none'; document.getElementById('2012.07668v1-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> 14 December, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">10 pages, 4 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/2011.01232">arXiv:2011.01232</a> <span> [<a href="https://arxiv.org/pdf/2011.01232">pdf</a>, <a href="https://arxiv.org/format/2011.01232">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> </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/abed5b">10.3847/1538-4357/abed5b <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Investigating Clumpy Galaxies in the Sloan Digital Sky Survey Stripe 82 using the Galaxy Zoo </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Mehta%2C+V">Vihang Mehta</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Adams%2C+D">Dominic Adams</a>, <a href="/search/astro-ph?searchtype=author&query=Chevallard%2C+J">Jacopo Chevallard</a>, <a href="/search/astro-ph?searchtype=author&query=Charlot%2C+S">St茅phane Charlot</a>, <a href="/search/astro-ph?searchtype=author&query=Beck%2C+M">Melanie Beck</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</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="2011.01232v2-abstract-short" style="display: inline;"> Giant, star-forming clumps are a common feature prevalent amongst high-redshift star-forming galaxies and play a critical role in shaping their chaotic morphologies and yet, their nature and role in galaxy evolution remains to be fully understood. A majority of the effort to study clumps has been focused at high redshifts, and local clump studies have often suffered from small sample sizes. In thi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2011.01232v2-abstract-full').style.display = 'inline'; document.getElementById('2011.01232v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2011.01232v2-abstract-full" style="display: none;"> Giant, star-forming clumps are a common feature prevalent amongst high-redshift star-forming galaxies and play a critical role in shaping their chaotic morphologies and yet, their nature and role in galaxy evolution remains to be fully understood. A majority of the effort to study clumps has been focused at high redshifts, and local clump studies have often suffered from small sample sizes. In this work, we present an analysis of clump properties in the local universe, and for the first time, performed with a statistically significant sample. With the help of the citizen science-powered Galaxy Zoo: Hubble project, we select a sample of 92 $z<0.06$ clumpy galaxies in Sloan Digital Sky Survey Stripe 82 galaxies. Within this sample, we identify 543 clumps using a contrast-based image analysis algorithm and perform photometry as well as estimate their stellar population properties. The overall properties of our $z<0.06$ clump sample are comparable to the high-redshift clumps. However, contrary to the high-redshift studies, we find no evidence of a gradient in clump ages or masses as a function of their galactocentric distances. Our results challenge the inward migration scenario for clump evolution for the local universe, potentially suggesting a larger contribution of ex-situ clumps and/or longer clump migration timescales. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2011.01232v2-abstract-full').style.display = 'none'; document.getElementById('2011.01232v2-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 April, 2021; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 November, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 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">21 pages, 16 figures; accepted for publication 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/2007.10295">arXiv:2007.10295</a> <span> [<a href="https://arxiv.org/pdf/2007.10295">pdf</a>, <a href="https://arxiv.org/format/2007.10295">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="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/s41550-020-1143-y">10.1038/s41550-020-1143-y <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Demonstration of stellar intensity interferometry with the four VERITAS telescopes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Davis%2C+J">J. Davis</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</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="2007.10295v1-abstract-short" style="display: inline;"> High angular resolution observations at optical wavelengths provide valuable insights in stellar astrophysics, directly measuring fundamental stellar parameters, and probing stellar atmospheres, circumstellar disks, elongation of rapidly rotating stars, and pulsations of Cepheid variable stars. The angular size of most stars are of order one milli-arcsecond or less, and to spatially resolve stella… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.10295v1-abstract-full').style.display = 'inline'; document.getElementById('2007.10295v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2007.10295v1-abstract-full" style="display: none;"> High angular resolution observations at optical wavelengths provide valuable insights in stellar astrophysics, directly measuring fundamental stellar parameters, and probing stellar atmospheres, circumstellar disks, elongation of rapidly rotating stars, and pulsations of Cepheid variable stars. The angular size of most stars are of order one milli-arcsecond or less, and to spatially resolve stellar disks and features at this scale requires an optical interferometer using an array of telescopes with baselines on the order of hundreds of meters. We report on the successful implementation of a stellar intensity interferometry system developed for the four VERITAS imaging atmospheric-Cherenkov telescopes. The system was used to measure the angular diameter of the two sub-mas stars $尾$ Canis Majoris and $蔚$ Orionis with a precision better than 5%. The system utilizes an off-line approach where starlight intensity fluctuations recorded at each telescope are correlated post-observation. The technique can be readily scaled onto tens to hundreds of telescopes, providing a capability that has proven technically challenging to current generation optical amplitude interferometry observatories. This work demonstrates the feasibility of performing astrophysical measurements with imaging atmospheric-Cherenkov telescope arrays as intensity interferometers and the promise for integrating an intensity interferometry system within future observatories such as the Cherenkov Telescope Array. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2007.10295v1-abstract-full').style.display = 'none'; document.getElementById('2007.10295v1-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 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">Accepted for publication in Nature Astronomy (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/2005.03110">arXiv:2005.03110</a> <span> [<a href="https://arxiv.org/pdf/2005.03110">pdf</a>, <a href="https://arxiv.org/format/2005.03110">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/ab910e">10.3847/1538-4357/ab910e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS Discovery of VHE Emission from the Radio Galaxy 3C 264: A Multi-Wavelength Study </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Carini%2C+M+T">M. T. Carini</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Errando%2C+M">M. Errando</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Fortin%2C+P">P. Fortin</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Georganopoulos%2C+M">M. Georganopoulos</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a> , et al. (45 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="2005.03110v1-abstract-short" style="display: inline;"> The radio source 3C 264, hosted by the giant elliptical galaxy NGC 3862, was observed with VERITAS between February 2017 and May 2019. These deep observations resulted in the discovery of very-high-energy (VHE; E $>100$ GeV) $纬$-ray emission from this active galaxy. An analysis of $\sim$57 hours of quality-selected live time yields a detection at the position of the source, corresponding to a stat… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.03110v1-abstract-full').style.display = 'inline'; document.getElementById('2005.03110v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2005.03110v1-abstract-full" style="display: none;"> The radio source 3C 264, hosted by the giant elliptical galaxy NGC 3862, was observed with VERITAS between February 2017 and May 2019. These deep observations resulted in the discovery of very-high-energy (VHE; E $>100$ GeV) $纬$-ray emission from this active galaxy. An analysis of $\sim$57 hours of quality-selected live time yields a detection at the position of the source, corresponding to a statistical significance of 7.8 standard deviations above background. The observed VHE flux is variable on monthly time scales, with an elevated flux seen in 2018 observations. The VHE emission during this elevated state is well-characterized by a power-law spectrum with a photon index $螕= 2.20 \pm 0.27$ and flux F($>315$ GeV) = ($7.6\pm 1.2_{\mathrm stat} \pm 2.3_{\mathrm syst})\times 10^{-13}$ cm$^{-2}$ s$^{-1}$, or approximately 0.7% of the Crab Nebula flux above the same threshold. 3C 264 ($z = 0.0217$) is the most distant radio galaxy detected at VHE, and the elevated state is thought to be similar to that of the famously outbursting jet in M 87. Consequently, extensive contemporaneous multi-wavelength data were acquired in 2018 at the time of the VHE high state. An analysis of these data, including VLBA, VLA, HST, Chandra and Swift observations in addition to the VERITAS data, is presented, along with a discussion of the resulting spectral energy distribution. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.03110v1-abstract-full').style.display = 'none'; document.getElementById('2005.03110v1-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 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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">19 pages, 11 figures, Accepted for publication in Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2003.13615">arXiv:2003.13615</a> <span> [<a href="https://arxiv.org/pdf/2003.13615">pdf</a>, <a href="https://arxiv.org/format/2003.13615">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/ab8310">10.3847/1538-4357/ab8310 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Evidence for proton acceleration up to TeV energies based on VERITAS and Fermi-LAT observations of the Cas A SNR </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Das%2C+S">S. Das</a>, <a href="/search/astro-ph?searchtype=author&query=Dwarkadas%2C+V+V">V. V. Dwarkadas</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</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="2003.13615v1-abstract-short" style="display: inline;"> We present a study of $纬$-ray emission from the core-collapse supernova remnant Cas~A in the energy range from 0.1GeV to 10TeV. We used 65 hours of VERITAS data to cover 200 GeV - 10 TeV, and 10.8 years of \textit{Fermi}-LAT data to cover 0.1-500 GeV. The spectral analysis of \textit{Fermi}-LAT data shows a significant spectral curvature around $1.3 \pm 0.4_{stat}$ GeV that is consistent with the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2003.13615v1-abstract-full').style.display = 'inline'; document.getElementById('2003.13615v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2003.13615v1-abstract-full" style="display: none;"> We present a study of $纬$-ray emission from the core-collapse supernova remnant Cas~A in the energy range from 0.1GeV to 10TeV. We used 65 hours of VERITAS data to cover 200 GeV - 10 TeV, and 10.8 years of \textit{Fermi}-LAT data to cover 0.1-500 GeV. The spectral analysis of \textit{Fermi}-LAT data shows a significant spectral curvature around $1.3 \pm 0.4_{stat}$ GeV that is consistent with the expected spectrum from pion decay. Above this energy, the joint spectrum from \textit{Fermi}-LAT and VERITAS deviates significantly from a simple power-law, and is best described by a power-law with spectral index of $2.17\pm 0.02_{stat}$ with a cut-off energy of $2.3 \pm 0.5_{stat}$ TeV. These results, along with radio, X-ray and $纬$-ray data, are interpreted in the context of leptonic and hadronic models. Assuming a one-zone model, we exclude a purely leptonic scenario and conclude that proton acceleration up to at least 6 TeV is required to explain the observed $纬$-ray spectrum. From modeling of the entire multi-wavelength spectrum, a minimum magnetic field inside the remnant of $B_{\mathrm{min}}\approx150\,\mathrm{渭G}$ is deduced. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2003.13615v1-abstract-full').style.display = 'none'; document.getElementById('2003.13615v1-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> 30 March, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">33 pages, 9 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/2002.04119">arXiv:2002.04119</a> <span> [<a href="https://arxiv.org/pdf/2002.04119">pdf</a>, <a href="https://arxiv.org/format/2002.04119">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/ab765d">10.3847/1538-4357/ab765d <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A decade of multi-wavelength observations of the TeV blazar 1ES 1215+303: Extreme shift of the synchrotron peak frequency and long-term optical-gamma-ray flux increase </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Valverde%2C+J">Janeth Valverde</a>, <a href="/search/astro-ph?searchtype=author&query=Horan%2C+D">Deirdre Horan</a>, <a href="/search/astro-ph?searchtype=author&query=Bernard%2C+D">Denis Bernard</a>, <a href="/search/astro-ph?searchtype=author&query=Fegan%2C+S">Stephen Fegan</a>, <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a> , et al. (64 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="2002.04119v2-abstract-short" style="display: inline;"> Blazars are known for their variability on a wide range of timescales at all wavelengths. Most studies of TeV gamma-ray blazars focus on short timescales, especially during flares. With a decade of observations from the Fermi-LAT and VERITAS, we present an extensive study of the long-term multi-wavelength radio-to-gamma-ray flux-density variability, with the addition of a couple of short-time radi… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.04119v2-abstract-full').style.display = 'inline'; document.getElementById('2002.04119v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2002.04119v2-abstract-full" style="display: none;"> Blazars are known for their variability on a wide range of timescales at all wavelengths. Most studies of TeV gamma-ray blazars focus on short timescales, especially during flares. With a decade of observations from the Fermi-LAT and VERITAS, we present an extensive study of the long-term multi-wavelength radio-to-gamma-ray flux-density variability, with the addition of a couple of short-time radio-structure and optical polarization observations of the blazar 1ES 1215+303 (z=0.130), with a focus on its gamma-ray emission from 100 MeV to 30 TeV. Multiple strong GeV gamma-ray flares, a long-term increase in the gamma-ray and optical flux baseline and a linear correlation between these two bands are observed over the ten-year period. Typical HBL behaviors are identified in the radio morphology and broadband spectrum of the source. Three stationary features in the innermost jet are resolved by VLBA at 43.1, 22.2, and 15.3 GHz. We employ a two-component synchrotron self-Compton model to describe different flux states of the source, including the epoch during which an extreme shift in energy of the synchrotron peak frequency from infrared to soft X-rays is observed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.04119v2-abstract-full').style.display = 'none'; document.getElementById('2002.04119v2-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 February, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 10 February, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">Accepted for publication in the Astrophysical Journal</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ApJ 891 (2020) 170 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2002.03567">arXiv:2002.03567</a> <span> [<a href="https://arxiv.org/pdf/2002.03567">pdf</a>, <a href="https://arxiv.org/format/2002.03567">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/ab6612">10.3847/1538-4357/ab6612 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Great Markarian 421 Flare of February 2010: Multiwavelength variability and correlation studies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Dumm%2C+J">J. Dumm</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Galante%2C+N">N. Galante</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a> , et al. (234 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="2002.03567v1-abstract-short" style="display: inline;"> We report on variability and correlation studies using multiwavelength observations of the blazar Mrk 421 during the month of February, 2010 when an extraordinary flare reaching a level of $\sim$27~Crab Units above 1~TeV was measured in very-high-energy (VHE) $纬$-rays with the VERITAS observatory. This is the highest flux state for Mrk 421 ever observed in VHE $纬$-rays. Data are analyzed from a co… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.03567v1-abstract-full').style.display = 'inline'; document.getElementById('2002.03567v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2002.03567v1-abstract-full" style="display: none;"> We report on variability and correlation studies using multiwavelength observations of the blazar Mrk 421 during the month of February, 2010 when an extraordinary flare reaching a level of $\sim$27~Crab Units above 1~TeV was measured in very-high-energy (VHE) $纬$-rays with the VERITAS observatory. This is the highest flux state for Mrk 421 ever observed in VHE $纬$-rays. Data are analyzed from a coordinated campaign across multiple instruments including VHE $纬$-ray (VERITAS, MAGIC), high-energy (HE) $纬$-ray (Fermi-LAT), X-ray (Swift}, RXTE, MAXI), optical (including the GASP-WEBT collaboration and polarization data) and radio (Mets盲hovi, OVRO, UMRAO). Light curves are produced spanning multiple days before and after the peak of the VHE flare, including over several flare `decline' epochs. The main flare statistics allow 2-minute time bins to be constructed in both the VHE and optical bands enabling a cross-correlation analysis that shows evidence for an optical lag of $\sim$25-55 minutes, the first time-lagged correlation between these bands reported on such short timescales. Limits on the Doppler factor ($未\gtrsim 33$) and the size of the emission region ($ 未^{-1}R_B \lesssim 3.8\times 10^{13}\,\,\mbox{cm}$) are obtained from the fast variability observed by VERITAS during the main flare. Analysis of 10-minute-binned VHE and X-ray data over the decline epochs shows an extraordinary range of behavior in the flux-flux relationship: from linear to quadratic to lack of correlation to anti-correlation. Taken together, these detailed observations of an unprecedented flare seen in Mrk 421 are difficult to explain by the classic single-zone synchrotron self-Compton model. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.03567v1-abstract-full').style.display = 'none'; document.getElementById('2002.03567v1-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> 10 February, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 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">41 pages including 3 appendices, 13 figures; version accepted to Astrophysical Journal</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 890, Number 2 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2001.03522">arXiv:2001.03522</a> <span> [<a href="https://arxiv.org/pdf/2001.03522">pdf</a>, <a href="https://arxiv.org/ps/2001.03522">ps</a>, <a href="https://arxiv.org/format/2001.03522">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/10.1016/j.astropartphys.2019.102403">10.1016/j.astropartphys.2019.102403 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS Detection of LS 5039 and HESS J1825-137 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=VERITAS+Collaboration"> VERITAS Collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kar%2C+P">P. Kar</a>, <a href="/search/astro-ph?searchtype=author&query=Kelley-Hoskins%2C+N">N. Kelley-Hoskins</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</a>, <a href="/search/astro-ph?searchtype=author&query=Krause%2C+M">M. Krause</a>, <a href="/search/astro-ph?searchtype=author&query=Lang%2C+M+J">M. J. Lang</a>, <a href="/search/astro-ph?searchtype=author&query=Maier%2C+G">G. Maier</a> , et al. (20 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="2001.03522v1-abstract-short" style="display: inline;"> With 8 hours of observations, VERITAS confirms the detection of two very high energy gamma-ray sources. The gamma-ray binary LS 5039 is detected with a statistical significance of $8.8蟽$. The measured flux above 1 TeV is $(2.5 \pm 0.4) \times 10^{-12} \rm \, cm^{-2} \, s^{-1}$ near inferior conjunction and $(7.8 \pm 2.8) \times 10^{-13} \rm \, cm^{-2} \, s^{-1}$ near superior conjunction. The puls… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2001.03522v1-abstract-full').style.display = 'inline'; document.getElementById('2001.03522v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2001.03522v1-abstract-full" style="display: none;"> With 8 hours of observations, VERITAS confirms the detection of two very high energy gamma-ray sources. The gamma-ray binary LS 5039 is detected with a statistical significance of $8.8蟽$. The measured flux above 1 TeV is $(2.5 \pm 0.4) \times 10^{-12} \rm \, cm^{-2} \, s^{-1}$ near inferior conjunction and $(7.8 \pm 2.8) \times 10^{-13} \rm \, cm^{-2} \, s^{-1}$ near superior conjunction. The pulsar wind nebula HESS J1825-137 is detected with a statistical significance of $6.7蟽$ and a measured flux above 1 TeV of $(3.9 \pm 0.8) \times 10^{-12} \rm \, cm^{-2} \, s^{-1}$. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2001.03522v1-abstract-full').style.display = 'none'; document.getElementById('2001.03522v1-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> 10 January, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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">4 pages, 2 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astroparticle Physics (2020), Volume 117, article id. 102403 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1911.09434">arXiv:1911.09434</a> <span> [<a href="https://arxiv.org/pdf/1911.09434">pdf</a>, <a href="https://arxiv.org/format/1911.09434">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/ab59de">10.3847/1538-4357/ab59de <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Probing the Properties of the Pulsar Wind in the Gamma-Ray Binary HESS J0632+057 with NuSTAR and VERITAS Observations </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</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="1911.09434v3-abstract-short" style="display: inline;"> HESS J0632+057 is a gamma-ray binary composed of a compact object orbiting a Be star with a period of about $315$ days. Extensive X-ray and TeV gamma-ray observations have revealed a peculiar light curve containing two peaks, separated by a dip. We present the results of simultaneous observations in hard X-rays with NuSTAR and in TeV gamma-rays with VERITAS, performed in November and December 2017… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.09434v3-abstract-full').style.display = 'inline'; document.getElementById('1911.09434v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1911.09434v3-abstract-full" style="display: none;"> HESS J0632+057 is a gamma-ray binary composed of a compact object orbiting a Be star with a period of about $315$ days. Extensive X-ray and TeV gamma-ray observations have revealed a peculiar light curve containing two peaks, separated by a dip. We present the results of simultaneous observations in hard X-rays with NuSTAR and in TeV gamma-rays with VERITAS, performed in November and December 2017. These observations correspond to the orbital phases $蠁\approx0.22$ and $0.3$, where the fluxes are rising towards the first light-curve peak. A significant variation of the spectral index from 1.77$\pm$0.05 to 1.56$\pm$0.05 is observed in the X-ray data. The multi-wavelength spectral energy distributions (SED) derived from the observations are interpreted in terms of a leptonic model, in which the compact object is assumed to be a pulsar and non-thermal radiation is emitted by high-energy electrons accelerated at the shock formed by the collision between the stellar and pulsar wind. The results of the SED fitting show that our data can be consistently described within this scenario, and allow us to estimate the magnetization of the pulsar wind at the location of the shock formation. The constraints on the pulsar-wind magnetization provided by our results are shown to be consistent with those obtained from other systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.09434v3-abstract-full').style.display = 'none'; document.getElementById('1911.09434v3-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 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 21 November, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 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 The Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1910.00451">arXiv:1910.00451</a> <span> [<a href="https://arxiv.org/pdf/1910.00451">pdf</a>, <a href="https://arxiv.org/format/1910.00451">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/ab4817">10.3847/1538-4357/ab4817 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Measurement of the extragalactic background light spectral energy distribution with VERITAS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=VERITAS+collaboration"> VERITAS collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Fernandez-Alonso%2C+M">M. Fernandez-Alonso</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a> , et al. (37 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="1910.00451v1-abstract-short" style="display: inline;"> The extragalactic background light (EBL), a diffuse photon field in the optical and infrared range, is a record of radiative processes over the Universe's history. Spectral measurements of blazars at very high energies ($>$100 GeV) enable the reconstruction of the spectral energy distribution (SED) of the EBL, as the blazar spectra are modified by redshift- and energy-dependent interactions of the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.00451v1-abstract-full').style.display = 'inline'; document.getElementById('1910.00451v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1910.00451v1-abstract-full" style="display: none;"> The extragalactic background light (EBL), a diffuse photon field in the optical and infrared range, is a record of radiative processes over the Universe's history. Spectral measurements of blazars at very high energies ($>$100 GeV) enable the reconstruction of the spectral energy distribution (SED) of the EBL, as the blazar spectra are modified by redshift- and energy-dependent interactions of the gamma-ray photons with the EBL. The spectra of 14 VERITAS-detected blazars are included in a new measurement of the EBL SED that is independent of EBL SED models. The resulting SED covers an EBL wavelength range of 0.56--56 $渭$m, and is in good agreement with lower limits obtained by assuming that the EBL is entirely due to radiation from cataloged galaxies. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1910.00451v1-abstract-full').style.display = 'none'; document.getElementById('1910.00451v1-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 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 for publication in The Astrophysical Journal</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1909.08114">arXiv:1909.08114</a> <span>  </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"> VERITAS contributions to the 36th International Cosmic Ray Conference </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Christiansen%2C+J+L">J. L. Christiansen</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Das%2C+S">S. Das</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a> , et al. (43 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="1909.08114v2-abstract-short" style="display: inline;"> Compilation of papers presented by the VERITAS Collaboration at the 36th International Cosmic Ray Conference (ICRC), held July 24 through August 1, 2019 in Madison, Wisconsin. </span> <span class="abstract-full has-text-grey-dark mathjax" id="1909.08114v2-abstract-full" style="display: none;"> Compilation of papers presented by the VERITAS Collaboration at the 36th International Cosmic Ray Conference (ICRC), held July 24 through August 1, 2019 in Madison, Wisconsin. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1909.08114v2-abstract-full').style.display = 'none'; document.getElementById('1909.08114v2-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 September, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 17 September, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 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">html page. 2019 ICRC, Madison, Wisconsin</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1905.07424">arXiv:1905.07424</a> <span> [<a href="https://arxiv.org/pdf/1905.07424">pdf</a>, <a href="https://arxiv.org/format/1905.07424">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="Computer Vision and Pattern Recognition">cs.CV</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/stz2816">10.1093/mnras/stz2816 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Galaxy Zoo: Probabilistic Morphology through Bayesian CNNs and Active Learning </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</a>, <a href="/search/astro-ph?searchtype=author&query=Smith%2C+L">Lewis Smith</a>, <a href="/search/astro-ph?searchtype=author&query=Lintott%2C+C">Chris Lintott</a>, <a href="/search/astro-ph?searchtype=author&query=Gal%2C+Y">Yarin Gal</a>, <a href="/search/astro-ph?searchtype=author&query=Bamford%2C+S">Steven Bamford</a>, <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Kruk%2C+S">Sandor Kruk</a>, <a href="/search/astro-ph?searchtype=author&query=Masters%2C+K">Karen Masters</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Simmons%2C+B">Brooke Simmons</a>, <a href="/search/astro-ph?searchtype=author&query=Smethurst%2C+R">Rebecca Smethurst</a>, <a href="/search/astro-ph?searchtype=author&query=Wright%2C+D">Darryl Wright</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="1905.07424v2-abstract-short" style="display: inline;"> We use Bayesian convolutional neural networks and a novel generative model of Galaxy Zoo volunteer responses to infer posteriors for the visual morphology of galaxies. Bayesian CNN can learn from galaxy images with uncertain labels and then, for previously unlabelled galaxies, predict the probability of each possible label. Our posteriors are well-calibrated (e.g. for predicting bars, we achieve c… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.07424v2-abstract-full').style.display = 'inline'; document.getElementById('1905.07424v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1905.07424v2-abstract-full" style="display: none;"> We use Bayesian convolutional neural networks and a novel generative model of Galaxy Zoo volunteer responses to infer posteriors for the visual morphology of galaxies. Bayesian CNN can learn from galaxy images with uncertain labels and then, for previously unlabelled galaxies, predict the probability of each possible label. Our posteriors are well-calibrated (e.g. for predicting bars, we achieve coverage errors of 11.8% within a vote fraction deviation of 0.2) and hence are reliable for practical use. Further, using our posteriors, we apply the active learning strategy BALD to request volunteer responses for the subset of galaxies which, if labelled, would be most informative for training our network. We show that training our Bayesian CNNs using active learning requires up to 35-60% fewer labelled galaxies, depending on the morphological feature being classified. By combining human and machine intelligence, Galaxy Zoo will be able to classify surveys of any conceivable scale on a timescale of weeks, providing massive and detailed morphology catalogues to support research into galaxy evolution. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1905.07424v2-abstract-full').style.display = 'none'; document.getElementById('1905.07424v2-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> 4 October, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 17 May, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 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 MNRAS. 21 pages, including appendices</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1904.09329">arXiv:1904.09329</a> <span> [<a href="https://arxiv.org/pdf/1904.09329">pdf</a>, <a href="https://arxiv.org/format/1904.09329">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/ab14f4">10.3847/1538-4357/ab14f4 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A Search for Pulsed Very High-Energy Gamma Rays from Thirteen Young Pulsars in Archival VERITAS Data </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+C+A">C. A. Johnson</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kar%2C+P">P. Kar</a>, <a href="/search/astro-ph?searchtype=author&query=Kelley-Hoskins%2C+N">N. Kelley-Hoskins</a> , et al. (36 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="1904.09329v1-abstract-short" style="display: inline;"> We conduct a search for periodic emission in the very high-energy gamma-ray band (VHE; E > 100 GeV) from a total of 13 pulsars in an archival VERITAS data set with a total exposure of over 450 hours. The set of pulsars includes many of the brightest young gamma-ray pulsars visible in the Northern Hemisphere. The data analysis resulted in non-detections of pulsed VHE gamma rays from each pulsar. Up… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.09329v1-abstract-full').style.display = 'inline'; document.getElementById('1904.09329v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.09329v1-abstract-full" style="display: none;"> We conduct a search for periodic emission in the very high-energy gamma-ray band (VHE; E > 100 GeV) from a total of 13 pulsars in an archival VERITAS data set with a total exposure of over 450 hours. The set of pulsars includes many of the brightest young gamma-ray pulsars visible in the Northern Hemisphere. The data analysis resulted in non-detections of pulsed VHE gamma rays from each pulsar. Upper limits on a potential VHE gamma-ray flux are derived at the 95% confidence level above three energy thresholds using two methods. These are the first such searches for pulsed VHE emission from each of the pulsars, and the obtained limits constrain a possible flux component manifesting at VHEs as is seen for the Crab pulsar. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.09329v1-abstract-full').style.display = 'none'; document.getElementById('1904.09329v1-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 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">32 pages, 20 figures, accepted for publication 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/1904.06324">arXiv:1904.06324</a> <span> [<a href="https://arxiv.org/pdf/1904.06324">pdf</a>, <a href="https://arxiv.org/format/1904.06324">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> <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/10.1038/s41550-019-0741-z">10.1038/s41550-019-0741-z <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Direct measurement of stellar angular diameters by the VERITAS Cherenkov Telescopes </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Giuri%2C+C">C. Giuri</a>, <a href="/search/astro-ph?searchtype=author&query=Gueta%2C+O">O. Gueta</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Halpern%2C+J">J. Halpern</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Joyce%2C+A+M">A. M. Joyce</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kar%2C+P">P. Kar</a>, <a href="/search/astro-ph?searchtype=author&query=Kelley-Hoskins%2C+N">N. Kelley-Hoskins</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</a> , et al. (32 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="1904.06324v1-abstract-short" style="display: inline;"> The angular size of a star is a critical factor in determining its basic properties. Direct measurement of stellar angular diameters is difficult: at interstellar distances stars are generally too small to resolve by any individual imaging telescope. This fundamental limitation can be overcome by studying the diffraction pattern in the shadow cast when an asteroid occults a star, but only when the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.06324v1-abstract-full').style.display = 'inline'; document.getElementById('1904.06324v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1904.06324v1-abstract-full" style="display: none;"> The angular size of a star is a critical factor in determining its basic properties. Direct measurement of stellar angular diameters is difficult: at interstellar distances stars are generally too small to resolve by any individual imaging telescope. This fundamental limitation can be overcome by studying the diffraction pattern in the shadow cast when an asteroid occults a star, but only when the photometric uncertainty is smaller than the noise added by atmospheric scintillation. Atmospheric Cherenkov telescopes used for particle astrophysics observations have not generally been exploited for optical astronomy due to the modest optical quality of the mirror surface. However, their large mirror area makes them well suited for such high-time-resolution precision photometry measurements. Here we report two occultations of stars observed by the VERITAS Cherenkov telescopes with millisecond sampling, from which we are able to provide a direct measurement of the occulted stars' angular diameter at the $\leq0.1$ milliarcsecond scale. This is a resolution never achieved before with optical measurements and represents an order of magnitude improvement over the equivalent lunar occultation method. We compare the resulting stellar radius with empirically derived estimates from temperature and brightness measurements, confirming the latter can be biased for stars with ambiguous stellar classifications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1904.06324v1-abstract-full').style.display = 'none'; document.getElementById('1904.06324v1-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 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 for publication in Nature Astronomy</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1903.07776">arXiv:1903.07776</a> <span> [<a href="https://arxiv.org/pdf/1903.07776">pdf</a>, <a href="https://arxiv.org/format/1903.07776">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="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/10.1017/S1743921319001418">10.1017/S1743921319001418 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Modeling with the Crowd: Optimizing the Human-Machine Partnership with Zooniverse </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Dickinson%2C+H">Hugh Dickinson</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">Lucy Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Scarlata%2C+C">Claudia Scarlata</a>, <a href="/search/astro-ph?searchtype=author&query=Beck%2C+M">Melanie Beck</a>, <a href="/search/astro-ph?searchtype=author&query=Walmsley%2C+M">Mike Walmsley</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="1903.07776v1-abstract-short" style="display: inline;"> LSST and Euclid must address the daunting challenge of analyzing the unprecedented volumes of imaging and spectroscopic data that these next-generation instruments will generate. A promising approach to overcoming this challenge involves rapid, automatic image processing using appropriately trained Deep Learning (DL) algorithms. However, reliable application of DL requires large, accurately labele… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.07776v1-abstract-full').style.display = 'inline'; document.getElementById('1903.07776v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.07776v1-abstract-full" style="display: none;"> LSST and Euclid must address the daunting challenge of analyzing the unprecedented volumes of imaging and spectroscopic data that these next-generation instruments will generate. A promising approach to overcoming this challenge involves rapid, automatic image processing using appropriately trained Deep Learning (DL) algorithms. However, reliable application of DL requires large, accurately labeled samples of training data. Galaxy Zoo Express (GZX) is a recent experiment that simulated using Bayesian inference to dynamically aggregate binary responses provided by citizen scientists via the Zooniverse crowd-sourcing platform in real time. The GZX approach enables collaboration between human and machine classifiers and provides rapidly generated, reliably labeled datasets, thereby enabling online training of accurate machine classifiers. We present selected results from GZX and show how the Bayesian aggregation engine it uses can be extended to efficiently provide object-localization and bounding-box annotations of two-dimensional data with quantified reliability. DL algorithms that are trained using these annotations will facilitate numerous panchromatic data modeling tasks including morphological classification and substructure detection in direct imaging, as well as decontamination and emission line identification for slitless spectroscopy. Effectively combining the speed of modern computational analyses with the human capacity to extrapolate from few examples will be critical if the potential of forthcoming large-scale surveys is to be realized. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.07776v1-abstract-full').style.display = 'none'; document.getElementById('1903.07776v1-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 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">5 pages, 1 figure. To appear in Proceedings of the International Astronomical Union</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/1810.05271">arXiv:1810.05271</a> <span> [<a href="https://arxiv.org/pdf/1810.05271">pdf</a>, <a href="https://arxiv.org/format/1810.05271">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/aae70e">10.3847/2041-8213/aae70e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Periastron Observations of TeV Gamma-Ray Emission from a Binary System with a 50-year Period </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=The+VERITAS+Collaboration"> The VERITAS Collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brill%2C+A">A. Brill</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gent%2C+A">A. Gent</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G+H">G. H. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hassan%2C+T">T. Hassan</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kar%2C+P">P. Kar</a>, <a href="/search/astro-ph?searchtype=author&query=Kertzman%2C+M">M. Kertzman</a>, <a href="/search/astro-ph?searchtype=author&query=Kieda%2C+D">D. Kieda</a> , et al. (191 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="1810.05271v1-abstract-short" style="display: inline;"> We report on observations of the pulsar / Be star binary system PSR J2032+4127 / MT91 213 in the energy range between 100 GeV and 20 TeV with the VERITAS and MAGIC imaging atmospheric Cherenkov telescope arrays. The binary orbit has a period of approximately 50 years, with the most recent periastron occurring on 2017 November 13. Our observations span from 18 months prior to periastron to one mont… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.05271v1-abstract-full').style.display = 'inline'; document.getElementById('1810.05271v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1810.05271v1-abstract-full" style="display: none;"> We report on observations of the pulsar / Be star binary system PSR J2032+4127 / MT91 213 in the energy range between 100 GeV and 20 TeV with the VERITAS and MAGIC imaging atmospheric Cherenkov telescope arrays. The binary orbit has a period of approximately 50 years, with the most recent periastron occurring on 2017 November 13. Our observations span from 18 months prior to periastron to one month after. A new, point-like, gamma-ray source is detected, coincident with the location of PSR J2032+4127 / MT91 213. The gamma-ray light curve and spectrum are well-characterized over the periastron passage. The flux is variable over at least an order of magnitude, peaking at periastron, thus providing a firm association of the TeV source with the pulsar / Be star system. Observations prior to periastron show a cutoff in the spectrum at an energy around 0.5 TeV. This result adds a new member to the small population of known TeV binaries, and it identifies only the second source of this class in which the nature and properties of the compact object are firmly established. We compare the gamma-ray results with the light curve measured with the X-ray Telescope (XRT) on board the Neil Gehrels \textit{Swift} Observatory and with the predictions of recent theoretical models of the system. We conclude that significant revision of the models is required to explain the details of the emission we have observed, and we discuss the relationship between the binary system and the overlapping steady extended source, TeV J2032+4130. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.05271v1-abstract-full').style.display = 'none'; document.getElementById('1810.05271v1-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, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">12 pages, 3 figures, 1 table. Accepted for publication 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, 867:L19 (8pp), 2018 November 1 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.10423">arXiv:1808.10423</a> <span> [<a href="https://arxiv.org/pdf/1808.10423">pdf</a>, <a href="https://arxiv.org/ps/1808.10423">ps</a>, <a href="https://arxiv.org/format/1808.10423">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/aade4e">10.3847/1538-4357/aade4e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> VERITAS and Fermi-LAT observations of new HAWC sources </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=VERITAS+Collaboration"> VERITAS Collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Abeysekara%2C+A+U">A. U. Abeysekara</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Bugaev%2C+V">V. Bugaev</a>, <a href="/search/astro-ph?searchtype=author&query=Chromey%2C+A+J">A. J. Chromey</a>, <a href="/search/astro-ph?searchtype=author&query=Connolly%2C+M+P">M. P. Connolly</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Daniel%2C+M+K">M. K. Daniel</a>, <a href="/search/astro-ph?searchtype=author&query=Falcone%2C+A">A. Falcone</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Hutten%2C+M">M. Hutten</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+C+A">C. A. Johnson</a> , et al. (259 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="1808.10423v1-abstract-short" style="display: inline;"> The HAWC (High Altitude Water Cherenkov) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100~GeV) gamma-ray sources based on 507 days of observation. Among these, there are nineteen sources that are not associated with previously known TeV sources. We have studied fourteen of these sources without known counterparts with VERITAS and Fermi-LAT. VERITAS detect… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.10423v1-abstract-full').style.display = 'inline'; document.getElementById('1808.10423v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.10423v1-abstract-full" style="display: none;"> The HAWC (High Altitude Water Cherenkov) collaboration recently published their 2HWC catalog, listing 39 very high energy (VHE; >100~GeV) gamma-ray sources based on 507 days of observation. Among these, there are nineteen sources that are not associated with previously known TeV sources. We have studied fourteen of these sources without known counterparts with VERITAS and Fermi-LAT. VERITAS detected weak gamma-ray emission in the 1~TeV-30~TeV band in the region of DA 495, a pulsar wind nebula coinciding with 2HWC J1953+294, confirming the discovery of the source by HAWC. We did not find any counterpart for the selected fourteen new HAWC sources from our analysis of Fermi-LAT data for energies higher than 10 GeV. During the search, we detected GeV gamma-ray emission coincident with a known TeV pulsar wind nebula, SNR G54.1+0.3 (VER J1930+188), and a 2HWC source, 2HWC J1930+188. The fluxes for isolated, steady sources in the 2HWC catalog are generally in good agreement with those measured by imaging atmospheric Cherenkov telescopes. However, the VERITAS fluxes for SNR G54.1+0.3, DA 495, and TeV J2032+4130 are lower than those measured by HAWC and several new HAWC sources are not detected by VERITAS. This is likely due to a change in spectral shape, source extension, or the influence of diffuse emission in the source region. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.10423v1-abstract-full').style.display = 'none'; document.getElementById('1808.10423v1-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> 30 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 for publication in the ApJ, Corresponding author: Nahee Park (VERITAS Collaboration), John W. Hewitt (Fermi-LAT Collaboration), Ignacio Taboada (HAWC Collaboration), 30 pages, 12 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ApJ 866 (2018) no.1, 24 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.10028">arXiv:1808.10028</a> <span> [<a href="https://arxiv.org/pdf/1808.10028">pdf</a>, <a href="https://arxiv.org/ps/1808.10028">ps</a>, <a href="https://arxiv.org/format/1808.10028">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/10.1103/PhysRevD.98.062004">10.1103/PhysRevD.98.062004 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Measurement of Cosmic-ray Electrons at TeV Energies by VERITAS </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=VERITAS+Collaboration"> VERITAS Collaboration</a>, <a href="/search/astro-ph?searchtype=author&query=Archer%2C+A">A. Archer</a>, <a href="/search/astro-ph?searchtype=author&query=Benbow%2C+W">W. Benbow</a>, <a href="/search/astro-ph?searchtype=author&query=Bird%2C+R">R. Bird</a>, <a href="/search/astro-ph?searchtype=author&query=Brose%2C+R">R. Brose</a>, <a href="/search/astro-ph?searchtype=author&query=Buchovecky%2C+M">M. Buchovecky</a>, <a href="/search/astro-ph?searchtype=author&query=Buckley%2C+J+H">J. H. Buckley</a>, <a href="/search/astro-ph?searchtype=author&query=Bugaev%2C+V">V. Bugaev</a>, <a href="/search/astro-ph?searchtype=author&query=Connolly%2C+M+P">M. P. Connolly</a>, <a href="/search/astro-ph?searchtype=author&query=Cui%2C+W">W. Cui</a>, <a href="/search/astro-ph?searchtype=author&query=Feng%2C+Q">Q. Feng</a>, <a href="/search/astro-ph?searchtype=author&query=Finley%2C+J+P">J. P. Finley</a>, <a href="/search/astro-ph?searchtype=author&query=Fortson%2C+L">L. Fortson</a>, <a href="/search/astro-ph?searchtype=author&query=Furniss%2C+A">A. Furniss</a>, <a href="/search/astro-ph?searchtype=author&query=Gillanders%2C+G">G. Gillanders</a>, <a href="/search/astro-ph?searchtype=author&query=H%C3%BCtten%2C+M">M. H眉tten</a>, <a href="/search/astro-ph?searchtype=author&query=Hanna%2C+D">D. Hanna</a>, <a href="/search/astro-ph?searchtype=author&query=Hervet%2C+O">O. Hervet</a>, <a href="/search/astro-ph?searchtype=author&query=Holder%2C+J">J. Holder</a>, <a href="/search/astro-ph?searchtype=author&query=Hughes%2C+G">G. Hughes</a>, <a href="/search/astro-ph?searchtype=author&query=Humensky%2C+T+B">T. B. Humensky</a>, <a href="/search/astro-ph?searchtype=author&query=Johnson%2C+C+A">C. A. Johnson</a>, <a href="/search/astro-ph?searchtype=author&query=Kaaret%2C+P">P. Kaaret</a>, <a href="/search/astro-ph?searchtype=author&query=Kar%2C+P">P. Kar</a>, <a href="/search/astro-ph?searchtype=author&query=Kelley-Hoskins%2C+N">N. Kelley-Hoskins</a> , et al. (36 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="1808.10028v1-abstract-short" style="display: inline;"> Cosmic-ray electrons and positrons (CREs) at GeV-TeV energies are a unique probe of our local Galactic neighborhood. CREs lose energy rapidly via synchrotron radiation and inverse-Compton scattering processes while propagating within the Galaxy and these losses limit their propagation distance. For electrons with TeV energies, the limit is on the order of a kiloparsec. Within that distance there a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.10028v1-abstract-full').style.display = 'inline'; document.getElementById('1808.10028v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.10028v1-abstract-full" style="display: none;"> Cosmic-ray electrons and positrons (CREs) at GeV-TeV energies are a unique probe of our local Galactic neighborhood. CREs lose energy rapidly via synchrotron radiation and inverse-Compton scattering processes while propagating within the Galaxy and these losses limit their propagation distance. For electrons with TeV energies, the limit is on the order of a kiloparsec. Within that distance there are only a few known astrophysical objects capable of accelerating electrons to such high energies. It is also possible that the CREs are the products of the annihilation or decay of heavy dark matter (DM) particles. VERITAS, an array of imaging air Cherenkov telescopes in southern Arizona, USA, is primarily utilized for gamma-ray astronomy, but also simultaneously collects CREs during all observations. We describe our methods of identifying CREs in VERITAS data and present an energy spectrum, extending from 300 GeV to 5 TeV, obtained from approximately 300 hours of observations. A single power-law fit is ruled out in VERITAS data. We find that the spectrum of CREs is consistent with a broken power law, with a break energy at 710 $\pm$ 40$_{stat}$ $\pm$ 140$_{syst}$ GeV. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.10028v1-abstract-full').style.display = 'none'; document.getElementById('1808.10028v1-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 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">17 pages, 2 figures, accepted for publication in PRD</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> 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