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class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2410.11960">arXiv:2410.11960</a> <span> [<a href="https://arxiv.org/pdf/2410.11960">pdf</a>, <a href="https://arxiv.org/format/2410.11960">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> <p class="title is-5 mathjax"> The Truncated Circumgalactic Medium of the Large Magellanic Cloud </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Mishra%2C+S">Sapna Mishra</a>, <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Krishnarao%2C+D">Dhanesh Krishnarao</a>, <a href="/search/?searchtype=author&query=Lucchini%2C+S">Scott Lucchini</a>, <a href="/search/?searchtype=author&query=D%27Onghia%2C+E">Elena D'Onghia</a>, <a href="/search/?searchtype=author&query=Cashman%2C+F+H">Frances H. Cashman</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Tumlinson%2C+J">Jason Tumlinson</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="2410.11960v1-abstract-short" style="display: inline;"> The Large Magellanic Cloud (LMC) is the nearest massive galaxy to the Milky Way. Its circumgalactic medium is complex and multi-phase, containing both stripped HI structures like the Magellanic Stream and Bridge, and a diffuse warm corona seen in high-ion absorption. We analyze 28 AGN sightlines passing within 35 kpc of the LMC with archival HST/COS spectra to characterize the cool (T\approx10^4$… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.11960v1-abstract-full').style.display = 'inline'; document.getElementById('2410.11960v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2410.11960v1-abstract-full" style="display: none;"> The Large Magellanic Cloud (LMC) is the nearest massive galaxy to the Milky Way. Its circumgalactic medium is complex and multi-phase, containing both stripped HI structures like the Magellanic Stream and Bridge, and a diffuse warm corona seen in high-ion absorption. We analyze 28 AGN sightlines passing within 35 kpc of the LMC with archival HST/COS spectra to characterize the cool (T\approx10^4$ K) gas in the LMC CGM, via new measurements of UV absorption in six low ions (OI, FeII, SiII, AlII, SII, and NiII) and one intermediate ion (SiIII). We show that a declining column-density profile is present in all seven ions, with the low-ion profiles having a steeper slope than the high-ion profiles in CIV and SiIV reported by Krishnarao et al. 2022. Crucially, absorption at the LMC systemic velocity is only detected (in all ions) out to 17 kpc. Beyond this distance, the gas has a lower velocity and is associated with the Magellanic Stream. These results demonstrate that the LMC's CGM is composed of two distinct components: a compact inner halo extending to 17 kpc, and a more extended stripped region associated with the Stream. The compactness and truncation of the LMC's inner CGM agree with recent simulations of ram-pressure stripping of the LMC by the Milky Way's extended corona. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2410.11960v1-abstract-full').style.display = 'none'; document.getElementById('2410.11960v1-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 October, 2024; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">Accepted for publication in 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/2305.09829">arXiv:2305.09829</a> <span> [<a href="https://arxiv.org/pdf/2305.09829">pdf</a>, <a href="https://arxiv.org/format/2305.09829">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/acc06e">10.3847/1538-4357/acc06e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Diffuse Ionized Gas of the Large Magellanic Cloud </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Smart%2C+B+M">B. M. Smart</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. M. Haffner</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=Ciampa%2C+D+A">D. A. Ciampa</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">A. S. Hill</a>, <a href="/search/?searchtype=author&query=Krishnarao%2C+D">D. Krishnarao</a>, <a href="/search/?searchtype=author&query=Madsen%2C+G+J">G. J. Madsen</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="2305.09829v1-abstract-short" style="display: inline;"> The Large Magellanic Cloud (LMC) has an extensive H$_伪$ emission halo that traces an extended, warm ionized component of its interstellar medium. Using the Wisconsin H$_伪$ Mapper (WHAM) telescope, we present the first kinematic \ha\ survey of an extensive region around the LMC, from $l,b = (264掳.5,\,-45掳.5)$ to $(295掳.5,\,-19掳.5)$, covering $+150\leq v_{lsr} \leq +390~ km s^{-1}$. We find that ion… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.09829v1-abstract-full').style.display = 'inline'; document.getElementById('2305.09829v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2305.09829v1-abstract-full" style="display: none;"> The Large Magellanic Cloud (LMC) has an extensive H$_伪$ emission halo that traces an extended, warm ionized component of its interstellar medium. Using the Wisconsin H$_伪$ Mapper (WHAM) telescope, we present the first kinematic \ha\ survey of an extensive region around the LMC, from $l,b = (264掳.5,\,-45掳.5)$ to $(295掳.5,\,-19掳.5)$, covering $+150\leq v_{lsr} \leq +390~ km s^{-1}$. We find that ionized hydrogen exists throughout the galaxy and extends several degrees beyond detected neutral hydrogen emission $(\log{\left(N_{\rm H_{~I}/\rm cm^{-2}}\right)\approx18.3})$ as traced by 21-cm in current surveys. Using the column density structure of the neutral gas and stellar line-of-sight depths as a guide, we estimate the upper limit mass of the ionized component of the LMC to be roughly $M_\mathrm{ionized}\approx (0.6-1.8)\times 10^{9}\,\mathrm{M}_{sun}$, which is comparable to the total neutral atomic gas mass in the same region ($M_\mathrm{neutral}\approx0.75-0.85\times10^{9}\,\mathrm{M}_{sun}$). Considering only the atomic phases, we find $M_\mathrm{ionized}/M_\mathrm{ionized+neutral}$, to be 46\%--68\% throughout the LMC and its extended halo. Additionally, we find an ionized gas cloud that extends off of the LMC at $l,b \approx (285掳, -28掳)$ into a region previously identified as the Leading Arm complex. This gas is moving at a similar line-of-sight velocity as the LMC and has $M_\mathrm{ionized}/M_\mathrm{ionized+neutral} =$ 13\%--51\%. This study, combined with previous studies of the SMC and extended structures of the Magellanic Clouds, continues to suggest that warm, ionized gas is as massive and dynamically-important as the neutral gas in the Magellanic System.$ <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2305.09829v1-abstract-full').style.display = 'none'; document.getElementById('2305.09829v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 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">20 pages, 12 figures, 4 tables</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ApJ 948 118 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2301.07688">arXiv:2301.07688</a> <span> [<a href="https://arxiv.org/pdf/2301.07688">pdf</a>, <a href="https://arxiv.org/format/2301.07688">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="Cosmology and Nongalactic Astrophysics">astro-ph.CO</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/10.3847/1538-4365/acda98">10.3847/1538-4365/acda98 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Eighteenth Data Release of the Sloan Digital Sky Surveys: Targeting and First Spectra from SDSS-V </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Almeida%2C+A">Andr茅s Almeida</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Argudo-Fern%C3%A1ndez%2C+M">Maria Argudo-Fern谩ndez</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J+K">Jorge K. Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Bender%2C+C+F">Chad F. Bender</a>, <a href="/search/?searchtype=author&query=Benitez%2C+E">Erika Benitez</a>, <a href="/search/?searchtype=author&query=Besser%2C+F">Felipe Besser</a>, <a href="/search/?searchtype=author&query=Bizyaev%2C+D">Dmitry Bizyaev</a>, <a href="/search/?searchtype=author&query=Blanton%2C+M+R">Michael R. Blanton</a>, <a href="/search/?searchtype=author&query=Bochanski%2C+J">John Bochanski</a>, <a href="/search/?searchtype=author&query=Bovy%2C+J">Jo Bovy</a>, <a href="/search/?searchtype=author&query=Brandt%2C+W+N">William Nielsen Brandt</a>, <a href="/search/?searchtype=author&query=Brownstein%2C+J+R">Joel R. Brownstein</a>, <a href="/search/?searchtype=author&query=Buchner%2C+J">Johannes Buchner</a>, <a href="/search/?searchtype=author&query=Bulbul%2C+E">Esra Bulbul</a>, <a href="/search/?searchtype=author&query=Burchett%2C+J+N">Joseph N. Burchett</a>, <a href="/search/?searchtype=author&query=D%C3%ADaz%2C+M+C">Mariana Cano D铆az</a>, <a href="/search/?searchtype=author&query=Carlberg%2C+J+K">Joleen K. Carlberg</a>, <a href="/search/?searchtype=author&query=Casey%2C+A+R">Andrew R. Casey</a>, <a href="/search/?searchtype=author&query=Chandra%2C+V">Vedant Chandra</a>, <a href="/search/?searchtype=author&query=Cherinka%2C+B">Brian Cherinka</a>, <a href="/search/?searchtype=author&query=Chiappini%2C+C">Cristina Chiappini</a>, <a href="/search/?searchtype=author&query=Coker%2C+A+A">Abigail A. Coker</a> , et al. (129 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="2301.07688v2-abstract-short" style="display: inline;"> The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM),… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.07688v2-abstract-full').style.display = 'inline'; document.getElementById('2301.07688v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2301.07688v2-abstract-full" style="display: none;"> The eighteenth data release of the Sloan Digital Sky Surveys (SDSS) is the first one for SDSS-V, the fifth generation of the survey. SDSS-V comprises three primary scientific programs, or "Mappers": Milky Way Mapper (MWM), Black Hole Mapper (BHM), and Local Volume Mapper (LVM). This data release contains extensive targeting information for the two multi-object spectroscopy programs (MWM and BHM), including input catalogs and selection functions for their numerous scientific objectives. We describe the production of the targeting databases and their calibration- and scientifically-focused components. DR18 also includes ~25,000 new SDSS spectra and supplemental information for X-ray sources identified by eROSITA in its eFEDS field. We present updates to some of the SDSS software pipelines and preview changes anticipated for DR19. We also describe three value-added catalogs (VACs) based on SDSS-IV data that have been published since DR17, and one VAC based on the SDSS-V data in the eFEDS field. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2301.07688v2-abstract-full').style.display = 'none'; document.getElementById('2301.07688v2-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 July, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 18 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">Accepted to ApJS</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2112.02026">arXiv:2112.02026</a> <span> [<a href="https://arxiv.org/pdf/2112.02026">pdf</a>, <a href="https://arxiv.org/format/2112.02026">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 class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4365/ac4414">10.3847/1538-4365/ac4414 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Seventeenth Data Release of the Sloan Digital Sky Surveys: Complete Release of MaNGA, MaStar and APOGEE-2 Data </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Abdurro%27uf"> Abdurro'uf</a>, <a href="/search/?searchtype=author&query=Accetta%2C+K">Katherine Accetta</a>, <a href="/search/?searchtype=author&query=Aerts%2C+C">Conny Aerts</a>, <a href="/search/?searchtype=author&query=Aguirre%2C+V+S">Victor Silva Aguirre</a>, <a href="/search/?searchtype=author&query=Ahumada%2C+R">Romina Ahumada</a>, <a href="/search/?searchtype=author&query=Ajgaonkar%2C+N">Nikhil Ajgaonkar</a>, <a href="/search/?searchtype=author&query=Ak%2C+N+F">N. Filiz Ak</a>, <a href="/search/?searchtype=author&query=Alam%2C+S">Shadab Alam</a>, <a href="/search/?searchtype=author&query=Prieto%2C+C+A">Carlos Allende Prieto</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Anders%2C+F">Friedrich Anders</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B+H">Brett H. Andrews</a>, <a href="/search/?searchtype=author&query=Anguiano%2C+B">Borja Anguiano</a>, <a href="/search/?searchtype=author&query=Aquino-Ortiz%2C+E">Erik Aquino-Ortiz</a>, <a href="/search/?searchtype=author&query=Aragon-Salamanca%2C+A">Alfonso Aragon-Salamanca</a>, <a href="/search/?searchtype=author&query=Argudo-Fernandez%2C+M">Maria Argudo-Fernandez</a>, <a href="/search/?searchtype=author&query=Ata%2C+M">Metin Ata</a>, <a href="/search/?searchtype=author&query=Aubert%2C+M">Marie Aubert</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Barba%2C+R+H">Rodolfo H. Barba</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J+K">Jorge K. Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Beaton%2C+R+L">Rachael L. Beaton</a> , et al. (316 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="2112.02026v2-abstract-short" style="display: inline;"> This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.02026v2-abstract-full').style.display = 'inline'; document.getElementById('2112.02026v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2112.02026v2-abstract-full" style="display: none;"> This paper documents the seventeenth data release (DR17) from the Sloan Digital Sky Surveys; the fifth and final release from the fourth phase (SDSS-IV). DR17 contains the complete release of the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey, which reached its goal of surveying over 10,000 nearby galaxies. The complete release of the MaNGA Stellar Library (MaStar) accompanies this data, providing observations of almost 30,000 stars through the MaNGA instrument during bright time. DR17 also contains the complete release of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) survey which publicly releases infra-red spectra of over 650,000 stars. The main sample from the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), as well as the sub-survey Time Domain Spectroscopic Survey (TDSS) data were fully released in DR16. New single-fiber optical spectroscopy released in DR17 is from the SPectroscipic IDentification of ERosita Survey (SPIDERS) sub-survey and the eBOSS-RM program. Along with the primary data sets, DR17 includes 25 new or updated Value Added Catalogs (VACs). This paper concludes the release of SDSS-IV survey data. SDSS continues into its fifth phase with observations already underway for the Milky Way Mapper (MWM), Local Volume Mapper (LVM) and Black Hole Mapper (BHM) surveys. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2112.02026v2-abstract-full').style.display = 'none'; document.getElementById('2112.02026v2-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, 2022; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 3 December, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">40 pages, 8 figures, 6 tables. In press at ApJSS (arxiv v2 corrects some minor typos and updates references)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2101.12129">arXiv:2101.12129</a> <span> [<a href="https://arxiv.org/pdf/2101.12129">pdf</a>, <a href="https://arxiv.org/format/2101.12129">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/abd320">10.3847/1538-4357/abd320 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Mapping the Supernovae Driven Winds of the Large Magellanic Cloud in H$伪$ Emission I </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Ciampa%2C+D+A">Drew A. Ciampa</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Horn%2C+M">Madeline Horn</a>, <a href="/search/?searchtype=author&query=Hernandez%2C+M">Michael Hernandez</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. Matthew Haffner</a>, <a href="/search/?searchtype=author&query=Smart%2C+B">Brianna Smart</a>, <a href="/search/?searchtype=author&query=Bustard%2C+C">Chad Bustard</a>, <a href="/search/?searchtype=author&query=Barber%2C+S">Sam Barber</a>, <a href="/search/?searchtype=author&query=Boot%2C+H">Henry Boot</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="2101.12129v1-abstract-short" style="display: inline;"> We present the first spectroscopically resolved \ha\ emission map of the Large Magellanic Cloud's (LMC) galactic wind. By combining new Wisconsin H-alpha Mapper (WHAM) observations ($I_{\rm H伪}\gtrsim10~{\rm mR}$) with existing \hicm\ emission observations, we have (1) mapped the LMC's near-side galactic wind over a local standard of rest (LSR) velocity range of… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.12129v1-abstract-full').style.display = 'inline'; document.getElementById('2101.12129v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2101.12129v1-abstract-full" style="display: none;"> We present the first spectroscopically resolved \ha\ emission map of the Large Magellanic Cloud's (LMC) galactic wind. By combining new Wisconsin H-alpha Mapper (WHAM) observations ($I_{\rm H伪}\gtrsim10~{\rm mR}$) with existing \hicm\ emission observations, we have (1) mapped the LMC's near-side galactic wind over a local standard of rest (LSR) velocity range of $+50\le\rm v_{LSR}\le+250~{\rm km}~{\rm s}^{-1}$, (2) determined its morphology and extent, and (3) estimated its mass, outflow rate, and mass-loading factor. We observe \ha\ emission from this wind to typically 1-degree off the LMC's \hi\ disk. Kinematically, we find that the diffuse gas in the warm-ionized phase of this wind persists at both low ($\lesssim100~{\rm km}~{\rm s}^{-1}$) and high ($\gtrsim100~{\rm km}~{\rm s}^{-1}$) velocities, relative to the LMC's \hi\ disk. Furthermore, we find that the high-velocity component spatially aligns with the most intense star-forming region, 30~Doradus. We, therefore, conclude that this high-velocity material traces an active outflow. We estimate the mass of the warm ($T_e\approx10^4~\rm K$) ionized phase of the near-side LMC outflow to be $\log{\left(M_{\rm ionized}/M_\odot\right)=7.51\pm0.15}$ for the combined low and high velocity components. Assuming an ionization fraction of 75\% and that the wind is symmetrical about the LMC disk, we estimate that its total (neutral and ionized) mass is $\log{\left(M_{\rm total}/M_\odot\right)=7.93}$, its mass-flow rate is $\dot{M}_{\rm outflow}\approx1.43~M_\odot~\rm yr^{-1}$, and its mass-loading factor is $畏\approx4.54$. Our average mass-loading factor results are roughly a factor of 2.5 larger than previous \ha\ imaging and UV~absorption line studies, suggesting that those studies are missing nearly half the gas in the outflows. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.12129v1-abstract-full').style.display = 'none'; document.getElementById('2101.12129v1-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 January, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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, 9 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/2101.11746">arXiv:2101.11746</a> <span> [<a href="https://arxiv.org/pdf/2101.11746">pdf</a>, <a href="https://arxiv.org/format/2101.11746">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/abb376">10.3847/1538-4357/abb376 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Exploring Hydrodynamic Instabilities along the Infalling High-Velocity Cloud Complex A </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Nidever%2C+D+L">David L. Nidever</a>, <a href="/search/?searchtype=author&query=Huey-You%2C+C">Cannan Huey-You</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Rueff%2C+K">Katherine Rueff</a>, <a href="/search/?searchtype=author&query=Freeman%2C+P">Paris Freeman</a>, <a href="/search/?searchtype=author&query=Birdwell%2C+A">Amber Birdwell</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">Joss Bland-Hawthorn</a>, <a href="/search/?searchtype=author&query=Benjamin%2C+R">Robert Benjamin</a>, <a href="/search/?searchtype=author&query=Ciampa%2C+D+A">Drew A. Ciampa</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="2101.11746v1-abstract-short" style="display: inline;"> Complex A is a high-velocity cloud that is traversing through the Galactic halo toward the Milky Way's disk. We combine both new and archival Green Bank Telescope observations to construct a spectroscopically resolved HI~21-cm map of this entire complex at a $17.1\lesssim\log{\left({N_{\rm HI},\,1蟽}/{\rm cm}^{-2}\right)}\lesssim17.9$ sensitivity for a ${\rm FWHM}=20~{\rm km}\,{\rm s}^{-1}$ line an… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.11746v1-abstract-full').style.display = 'inline'; document.getElementById('2101.11746v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2101.11746v1-abstract-full" style="display: none;"> Complex A is a high-velocity cloud that is traversing through the Galactic halo toward the Milky Way's disk. We combine both new and archival Green Bank Telescope observations to construct a spectroscopically resolved HI~21-cm map of this entire complex at a $17.1\lesssim\log{\left({N_{\rm HI},\,1蟽}/{\rm cm}^{-2}\right)}\lesssim17.9$ sensitivity for a ${\rm FWHM}=20~{\rm km}\,{\rm s}^{-1}$ line and $螖胃=9.1\,{\rm arcmins}$ or $17\lesssim螖d_胃\lesssim30~\rm pc$ spatial resolution. We find that that Complex A is has a Galactic standard of rest frame velocity gradient of $螖\rm v_{GSR}/螖L=25~{\rm km}\,{\rm s}^{-1}/{\rm kpc}$ along its length, that it is decelerating at a rate of $\langle a\rangle_{\rm GSR}=55~{\rm km}/{\rm yr}^2$, and that it will reach the Galactic plane in $螖t\lesssim70~{\rm Myrs}$ if it can survive the journey. We have identify numerous signatures of gas disruption. The elongated and multi-core structure of Complex A indicates that either thermodynamic instabilities or shock-cascade processes have fragmented this stream. We find Rayleigh-Taylor fingers on the low-latitude edge of this HVC; many have been pushed backward by ram-pressure stripping. On the high-latitude side of the complex, Kelvin-Helmholtz instabilities have generated two large wings that extend tangentially off Complex A. The tips of these wings curve slightly forward in the direction of motion and have an elevated \hi\ column density, indicating that these wings are forming Rayleigh-Taylor globules at their tips and that this gas is becoming entangled with unseen vortices in the surrounding coronal gas. These observations provide new insights on the survivability of low-metallicity gas streams that are accreting onto $L_\star$ galaxies. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2101.11746v1-abstract-full').style.display = 'none'; document.getElementById('2101.11746v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 January, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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">Figure 5 of the paper is a video in the published that can be found here: https://www.youtube.com/watch?v=YSbJetacspo</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> ApJ, 902, 154 (2020) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2005.05720">arXiv:2005.05720</a> <span> [<a href="https://arxiv.org/pdf/2005.05720">pdf</a>, <a href="https://arxiv.org/format/2005.05720">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/ab92a3">10.3847/1538-4357/ab92a3 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Kinematics of the Magellanic Stream and Implications for its Ionization </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Frazer%2C+E+M">Elaine M. Frazer</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">Joss Bland-Hawthorn</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Richter%2C+P">Philipp Richter</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="2005.05720v1-abstract-short" style="display: inline;"> The Magellanic Stream and the Leading Arm form a massive, filamentary system of gas clouds surrounding the Large and Small Magellanic Clouds. Here we present a new component-level analysis of their ultraviolet (UV) kinematic properties using a sample of 31 sightlines through the Magellanic System observed with the Hubble Space Telescope/Cosmic Origins Spectrograph. Using Voigt profile fits to UV m… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.05720v1-abstract-full').style.display = 'inline'; document.getElementById('2005.05720v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2005.05720v1-abstract-full" style="display: none;"> The Magellanic Stream and the Leading Arm form a massive, filamentary system of gas clouds surrounding the Large and Small Magellanic Clouds. Here we present a new component-level analysis of their ultraviolet (UV) kinematic properties using a sample of 31 sightlines through the Magellanic System observed with the Hubble Space Telescope/Cosmic Origins Spectrograph. Using Voigt profile fits to UV metal-line absorption, we quantify the kinematic differences between the low-ion (Si II and C II), intermediate-ion (Si III), and high-ion (Si IV and C IV) absorption lines and compare the kinematics between the Stream and Leading Arm. We find that the Stream shows generally simple, single-phase kinematics, with statistically indistinguishable b-value distributions for the low-, intermediate-, and high-ion components, all dominated by narrow (b<25 km/s) components that are well aligned in velocity. In contrast, we find tentative evidence that the Leading Arm shows complex, multi-phase kinematics, with broader high ions than low ions. These results suggest that the Stream is photoionized up to C IV by a hard ionizing radiation field. This can be naturally explained by the Seyfert-flare model of Bland-Hawthorn et al. (2013, 2019), in which a burst of ionizing radiation from the Galactic Center photoionized the Stream as it passed below the south Galactic pole. The Seyfert flare is the only known source of radiation that is both powerful enough to explain the H-alpha intensity of the Stream and hard enough to photoionize Si IV and C IV to the observed levels. The flare's timescale of a few Myr suggests it is the same event that created the giant X-ray/gamma-ray Fermi Bubbles at the Galactic Center. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2005.05720v1-abstract-full').style.display = 'none'; document.getElementById('2005.05720v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 12 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">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">Accepted for publication in ApJ. 22 pages, 6 figures, 4 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/2004.09606">arXiv:2004.09606</a> <span> [<a href="https://arxiv.org/pdf/2004.09606">pdf</a>, <a href="https://arxiv.org/format/2004.09606">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/ab6ef9">10.3847/1538-4357/ab6ef9 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> H$伪$ Distances to the Leading Arm of the Magellanic Stream </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Antwi-Danso%2C+J">Jacqueline Antwi-Danso</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. Matthew Haffner</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2004.09606v1-abstract-short" style="display: inline;"> The Leading Arm is a tidal feature that is in front of the Magellanic Clouds on their orbit through the Galaxy's halo. Many physical properties of the Leading Arm, such as its mass and size, are poorly constrained because it has few distance measurements. While H$伪$ measurements have been used to estimate the distances to halo clouds, many studies have been unsuccessful in detecting H$伪$ from the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.09606v1-abstract-full').style.display = 'inline'; document.getElementById('2004.09606v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2004.09606v1-abstract-full" style="display: none;"> The Leading Arm is a tidal feature that is in front of the Magellanic Clouds on their orbit through the Galaxy's halo. Many physical properties of the Leading Arm, such as its mass and size, are poorly constrained because it has few distance measurements. While H$伪$ measurements have been used to estimate the distances to halo clouds, many studies have been unsuccessful in detecting H$伪$ from the Leading Arm. In this study, we explore a group of H I clouds which lie $75^{\circ} - 90^{\circ}$ from the Magellanic Clouds. Through ultraviolet and 21-cm radio spectroscopy, this region, dubbed the Leading Arm Extension, was found to have chemical and kinematic similarities to the Leading Arm. Using the Wisconsin H$伪$ Mapper, we detect H$伪$ emission in four out of seven of our targets. Assuming that this region is predominantly photoionized, we use a radiation model that incorporates the contributions of the Galaxy, Magellanic Clouds, and the extragalactic background at $\rm z = 0$ to derive a heliocentric distance of $d_{\odot}\ge13.4~kpc$. We also use this model to rederive H$伪$ distances of $d_{\odot} \geq 5.0$ kpc and $d_{\odot} \geq 22.9~kpc$ to two clouds in the literature that might also be associated with the Leading Arm. Using these new measurements, and others in the literature, we provide a general trend of the variation of Leading Arm heliocentric distance as a function of Magellanic Stream longitude, and explore its implications for the origin and closest point of approach of the Leading Arm. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2004.09606v1-abstract-full').style.display = 'none'; document.getElementById('2004.09606v1-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 April, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">13 pages, 5 figures, published 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/2002.07818">arXiv:2002.07818</a> <span> [<a href="https://arxiv.org/pdf/2002.07818">pdf</a>, <a href="https://arxiv.org/format/2002.07818">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/aba49c">10.3847/1538-4357/aba49c <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Project AMIGA: The Circumgalactic Medium of Andromeda </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Berek%2C+S+C">Samantha C. Berek</a>, <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. Christopher Howk</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Tumlinson%2C+J">Jason Tumlinson</a>, <a href="/search/?searchtype=author&query=Jenkins%2C+E+B">Edward B. Jenkins</a>, <a href="/search/?searchtype=author&query=Prochaska%2C+J+X">J. Xavier Prochaska</a>, <a href="/search/?searchtype=author&query=Augustin%2C+R">Ramona Augustin</a>, <a href="/search/?searchtype=author&query=Ji%2C+S">Suoqing Ji</a>, <a href="/search/?searchtype=author&query=Faucher-Giguere%2C+C">Claude-Andre Faucher-Giguere</a>, <a href="/search/?searchtype=author&query=Hafen%2C+Z">Zachary Hafen</a>, <a href="/search/?searchtype=author&query=Peeples%2C+M+S">Molly S. Peeples</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kat A. Barger</a>, <a href="/search/?searchtype=author&query=Berg%2C+M+A">Michelle A. Berg</a>, <a href="/search/?searchtype=author&query=Bordoloi%2C+R">Rongmon Bordoloi</a>, <a href="/search/?searchtype=author&query=Brown%2C+T+M">Thomas M. Brown</a>, <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Gilbert%2C+K+M">Karoline M. Gilbert</a>, <a href="/search/?searchtype=author&query=Guhathakurta%2C+P">Puragra Guhathakurta</a>, <a href="/search/?searchtype=author&query=Kalirai%2C+J+S">Jason S. Kalirai</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">Felix J. Lockman</a>, <a href="/search/?searchtype=author&query=O%27Meara%2C+J+M">John M. O'Meara</a>, <a href="/search/?searchtype=author&query=Pisano%2C+D+J">D. J. Pisano</a>, <a href="/search/?searchtype=author&query=Ribaudo%2C+J">Joseph Ribaudo</a>, <a href="/search/?searchtype=author&query=Werk%2C+J+K">Jessica K. Werk</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="2002.07818v1-abstract-short" style="display: inline;"> Project AMIGA (Absorption Maps In the Gas of Andromeda) is a large ultraviolet Hubble Space Telescope program, which has assembled a sample of 43 QSOs that pierce the circumgalactic medium (CGM) of Andromeda (M31) from R=25 to 569 kpc (25 of them probing gas from 25 kpc to about the virial radius-Rvir = 300 kpc-of M31). Our large sample provides an unparalleled look at the physical conditions and… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.07818v1-abstract-full').style.display = 'inline'; document.getElementById('2002.07818v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2002.07818v1-abstract-full" style="display: none;"> Project AMIGA (Absorption Maps In the Gas of Andromeda) is a large ultraviolet Hubble Space Telescope program, which has assembled a sample of 43 QSOs that pierce the circumgalactic medium (CGM) of Andromeda (M31) from R=25 to 569 kpc (25 of them probing gas from 25 kpc to about the virial radius-Rvir = 300 kpc-of M31). Our large sample provides an unparalleled look at the physical conditions and distribution of metals in the CGM of a single galaxy using ions that probe a wide range of gas phases (Si II, Si III, Si IV, C II, C IV, and O VI, the latter being from the Far Ultraviolet Spectroscopic Explorer). We find that Si III and O VI have near unity covering factor maintained all the way out to 1.2Rvir and 1.9Rvir, respectively. We show that Si III is the dominant ion over Si II and Si IV at any R. While we do not find that the properties of the CGM of M31 depend strongly on the azimuth, we show that they change remarkably around 0.3-0.5Rvir, conveying that the inner regions of the CGM of M31 are more dynamic and have more complicated multi-phase gas-structures than at R>0.5Rvir. We estimate the metal mass of the CGM within Rvir as probed by Si II, Si III, and Si IV is 2x10^7 Msun and by O VI is >8x10^7 Msun, while the baryon mass of the 10^4-10^5.5 K gas is ~4x10^10 (Z/0.3 Zsun)^(-1) Msun within Rvir. We show that different zoom-in cosmological simulations of L* galaxies better reproduce the column density profile of O VI with R than Si III or the other studied ions. We find that observations of the M31 CGM and zoom-in simulations of L* galaxies have both lower ions showing higher column density dispersion and dependence on R than higher ions, indicating that the higher ionization structures are larger and/or more broadly distributed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2002.07818v1-abstract-full').style.display = 'none'; document.getElementById('2002.07818v1-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 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">Submitted to the Astrophysical Journal. Comments welcome</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1912.02905">arXiv:1912.02905</a> <span> [<a href="https://arxiv.org/pdf/1912.02905">pdf</a>, <a href="https://arxiv.org/format/1912.02905">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="Cosmology and Nongalactic Astrophysics">astro-ph.CO</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/10.3847/1538-4365/ab929e">10.3847/1538-4365/ab929e <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Sixteenth Data Release of the Sloan Digital Sky Surveys: First Release from the APOGEE-2 Southern Survey and Full Release of eBOSS Spectra </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Ahumada%2C+R">Romina Ahumada</a>, <a href="/search/?searchtype=author&query=Prieto%2C+C+A">Carlos Allende Prieto</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Anders%2C+F">Friedrich Anders</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B+H">Brett H. Andrews</a>, <a href="/search/?searchtype=author&query=Anguiano%2C+B">Borja Anguiano</a>, <a href="/search/?searchtype=author&query=Arcodia%2C+R">Riccardo Arcodia</a>, <a href="/search/?searchtype=author&query=Armengaud%2C+E">Eric Armengaud</a>, <a href="/search/?searchtype=author&query=Aubert%2C+M">Marie Aubert</a>, <a href="/search/?searchtype=author&query=Avila%2C+S">Santiago Avila</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Balland%2C+C">Christophe Balland</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J+K">Jorge K. Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Basu%2C+S">Sarbani Basu</a>, <a href="/search/?searchtype=author&query=Bautista%2C+J">Julian Bautista</a>, <a href="/search/?searchtype=author&query=Beaton%2C+R+L">Rachael L. Beaton</a>, <a href="/search/?searchtype=author&query=Beers%2C+T+C">Timothy C. Beers</a>, <a href="/search/?searchtype=author&query=Benavides%2C+B+I+T">B. Izamar T. Benavides</a>, <a href="/search/?searchtype=author&query=Bender%2C+C+F">Chad F. Bender</a>, <a href="/search/?searchtype=author&query=Bernardi%2C+M">Mariangela Bernardi</a>, <a href="/search/?searchtype=author&query=Bershady%2C+M">Matthew Bershady</a>, <a href="/search/?searchtype=author&query=Beutler%2C+F">Florian Beutler</a> , et al. (289 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="1912.02905v2-abstract-short" style="display: inline;"> This paper documents the sixteenth data release (DR16) from the Sloan Digital Sky Surveys; the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the southern hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.02905v2-abstract-full').style.display = 'inline'; document.getElementById('1912.02905v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1912.02905v2-abstract-full" style="display: none;"> This paper documents the sixteenth data release (DR16) from the Sloan Digital Sky Surveys; the fourth and penultimate from the fourth phase (SDSS-IV). This is the first release of data from the southern hemisphere survey of the Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2); new data from APOGEE-2 North are also included. DR16 is also notable as the final data release for the main cosmological program of the Extended Baryon Oscillation Spectroscopic Survey (eBOSS), and all raw and reduced spectra from that project are released here. DR16 also includes all the data from the Time Domain Spectroscopic Survey (TDSS) and new data from the SPectroscopic IDentification of ERosita Survey (SPIDERS) programs, both of which were co-observed on eBOSS plates. DR16 has no new data from the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey (or the MaNGA Stellar Library "MaStar"). We also preview future SDSS-V operations (due to start in 2020), and summarize plans for the final SDSS-IV data release (DR17). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1912.02905v2-abstract-full').style.display = 'none'; document.getElementById('1912.02905v2-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 May, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 5 December, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">DR16 release: Monday Dec 9th 2019. This is the alphabetical order SDSS-IV collaboration data release paper. 25 pages, 6 figures, accepted by ApJS on 11th May 2020. Minor changes clarify or improve text and figures relative to v1</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1911.11588">arXiv:1911.11588</a> <span> [<a href="https://arxiv.org/pdf/1911.11588">pdf</a>, <a href="https://arxiv.org/format/1911.11588">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/ab4d58">10.3847/1538-4357/ab4d58 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Diffuse Ionized Gas Halo of the Small Magellanic Cloud </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Smart%2C+B+M">Brianna M Smart</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">Lawrence M Haffner</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Hill%2C+A">Alex Hill</a>, <a href="/search/?searchtype=author&query=Madsen%2C+G">Greg Madsen</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="1911.11588v2-abstract-short" style="display: inline;"> Observations with the Wisconsin H-alpha Mapper (WHAM) reveal a large, diffuse ionized halo that surrounds the Small Magellanic Cloud (SMC). We present the first kinematic H-alpha survey of an extended region around the galaxy, from (l,b) = (289.5,-35.0) to (315.1,-5.3) and covering +90 <= vLSR <= +210 km s-1. The ionized gas emission extends far beyond the central stellar component of the galaxy,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.11588v2-abstract-full').style.display = 'inline'; document.getElementById('1911.11588v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1911.11588v2-abstract-full" style="display: none;"> Observations with the Wisconsin H-alpha Mapper (WHAM) reveal a large, diffuse ionized halo that surrounds the Small Magellanic Cloud (SMC). We present the first kinematic H-alpha survey of an extended region around the galaxy, from (l,b) = (289.5,-35.0) to (315.1,-5.3) and covering +90 <= vLSR <= +210 km s-1. The ionized gas emission extends far beyond the central stellar component of the galaxy, reaching similar distances to that of the diffuse neutral halo traced by 21 cm observations. H-alpha emission extends several degrees beyond the sensitivity of current H I surveys toward smaller Galactic longitudes and more negative Galactic latitudes. The velocity field of the ionized gas near the SMC appears similar to to the neutral halo of the galaxy. Using the observed emission measure as a guide, we estimate the mass of this newly revealed ionized component to be roughly (0.8 - 1.0) x 10^9 M_sun, which is comparable to the total neutral mass in the same region of (0.9 - 1.1) x 10^9 M_sun. We find ratios of the total ionized gas mass divided by the total neutral plus ionized gas mass in three distinct subregions to be: (1) 46%-54% throughout the SMC and its extended halo, (2) 12%-32% in the SMC Tail that extends toward the Magellanic Bridge, and (3) 65%-79% in a filament that extends away from the SMC toward the Magellanic Stream. This newly discovered, coherent H-alpha filament does not appear to have a well-structured neutral component and is also not coincident with two previously identified filaments traced by 21 cm emission within the Stream. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1911.11588v2-abstract-full').style.display = 'none'; document.getElementById('1911.11588v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 27 November, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 26 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">16 pages, 8 figures, 3 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/1903.04831">arXiv:1903.04831</a> <span> [<a href="https://arxiv.org/pdf/1903.04831">pdf</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> <p class="title is-5 mathjax"> The Magellanic Stream as a Probe of Astrophysics </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">Joss Bland-Hawthorn</a>, <a href="/search/?searchtype=author&query=Casetti-Dinescu%2C+D">Dana Casetti-Dinescu</a>, <a href="/search/?searchtype=author&query=D%27Onghia%2C+E">Elena D'Onghia</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">Felix J. Lockman</a>, <a href="/search/?searchtype=author&query=McClure-Griffiths%2C+N">Naomi McClure-Griffiths</a>, <a href="/search/?searchtype=author&query=Nidever%2C+D">David Nidever</a>, <a href="/search/?searchtype=author&query=Putman%2C+M">Mary Putman</a>, <a href="/search/?searchtype=author&query=Richter%2C+P">Philipp Richter</a>, <a href="/search/?searchtype=author&query=Stanimirovic%2C+S">Snezana Stanimirovic</a>, <a href="/search/?searchtype=author&query=Tepper-Garcia%2C+T">Thorsten Tepper-Garcia</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="1903.04831v1-abstract-short" style="display: inline;"> Extending for over 200 degrees across the sky, the Magellanic Stream together with its Leading Arm is the most spectacular example of a gaseous stream in the local Universe. The Stream is an interwoven tail of filaments trailing the Magellanic Clouds as they orbit the Milky Way. Thought to be created by tidal forces, ram pressure, and halo interactions, the Stream is a benchmark for dynamical mode… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.04831v1-abstract-full').style.display = 'inline'; document.getElementById('1903.04831v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1903.04831v1-abstract-full" style="display: none;"> Extending for over 200 degrees across the sky, the Magellanic Stream together with its Leading Arm is the most spectacular example of a gaseous stream in the local Universe. The Stream is an interwoven tail of filaments trailing the Magellanic Clouds as they orbit the Milky Way. Thought to be created by tidal forces, ram pressure, and halo interactions, the Stream is a benchmark for dynamical models of the Magellanic System, a case study for gas accretion and dwarf-galaxy accretion onto galaxies, a probe of the outer halo, and the bearer of more gas mass than all other Galactic high velocity clouds combined. If it survives to reach the Galactic disk, it may maintain or even elevate the Galactic star-formation rate. In this white paper, we emphasize the Stream's importance for many areas of Galactic astronomy, summarize key unanswered questions, and identify future observations and simulations needed to resolve them. We stress the importance of ultraviolet, optical, and radio spectroscopy, and the need for computational models that capture full particle and radiation treatments within an MHD environment. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1903.04831v1-abstract-full').style.display = 'none'; document.getElementById('1903.04831v1-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 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">Science White Paper submitted to Astro2020 Decadal Survey. 7 pages, 2 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/1812.02759">arXiv:1812.02759</a> <span> [<a href="https://arxiv.org/pdf/1812.02759">pdf</a>, <a href="https://arxiv.org/format/1812.02759">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/10.3847/1538-4365/aaf651">10.3847/1538-4365/aaf651 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Fifteenth Data Release of the Sloan Digital Sky Surveys: First Release of MaNGA Derived Quantities, Data Visualization Tools and Stellar Library </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Aguado%2C+D+S">D. S. Aguado</a>, <a href="/search/?searchtype=author&query=Ahumada%2C+R">Romina Ahumada</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B+H">Brett H. Andrews</a>, <a href="/search/?searchtype=author&query=Anguiano%2C+B">Borja Anguiano</a>, <a href="/search/?searchtype=author&query=Ortiz%2C+E+A">Erik Aquino Ortiz</a>, <a href="/search/?searchtype=author&query=Aragon-Salamanca%2C+A">Alfonso Aragon-Salamanca</a>, <a href="/search/?searchtype=author&query=Argudo-Fernandez%2C+M">Maria Argudo-Fernandez</a>, <a href="/search/?searchtype=author&query=Aubert%2C+M">Marie Aubert</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Rembold%2C+S+B">Sandro Barboza Rembold</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J">Jorge Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Bates%2C+D">Dominic Bates</a>, <a href="/search/?searchtype=author&query=Bautista%2C+J">Julian Bautista</a>, <a href="/search/?searchtype=author&query=Beaton%2C+R+L">Rachael L. Beaton</a>, <a href="/search/?searchtype=author&query=Beers%2C+T+C">Timothy C. Beers</a>, <a href="/search/?searchtype=author&query=Belfiore%2C+F">Francesco Belfiore</a>, <a href="/search/?searchtype=author&query=Bernardi%2C+M">Mariangela Bernardi</a>, <a href="/search/?searchtype=author&query=Bershady%2C+M">Matthew Bershady</a>, <a href="/search/?searchtype=author&query=Beutler%2C+F">Florian Beutler</a>, <a href="/search/?searchtype=author&query=Bird%2C+J">Jonathan Bird</a>, <a href="/search/?searchtype=author&query=Bizyaev%2C+D">Dmitry Bizyaev</a> , et al. (209 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="1812.02759v2-abstract-short" style="display: inline;"> Twenty years have passed since first light for the Sloan Digital Sky Survey (SDSS). Here, we release data taken by the fourth phase of SDSS (SDSS-IV) across its first three years of operation (July 2014-July 2017). This is the third data release for SDSS-IV, and the fifteenth from SDSS (Data Release Fifteen; DR15). New data come from MaNGA - we release 4824 datacubes, as well as the first stellar… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1812.02759v2-abstract-full').style.display = 'inline'; document.getElementById('1812.02759v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1812.02759v2-abstract-full" style="display: none;"> Twenty years have passed since first light for the Sloan Digital Sky Survey (SDSS). Here, we release data taken by the fourth phase of SDSS (SDSS-IV) across its first three years of operation (July 2014-July 2017). This is the third data release for SDSS-IV, and the fifteenth from SDSS (Data Release Fifteen; DR15). New data come from MaNGA - we release 4824 datacubes, as well as the first stellar spectra in the MaNGA Stellar Library (MaStar), the first set of survey-supported analysis products (e.g. stellar and gas kinematics, emission line, and other maps) from the MaNGA Data Analysis Pipeline (DAP), and a new data visualisation and access tool we call "Marvin". The next data release, DR16, will include new data from both APOGEE-2 and eBOSS; those surveys release no new data here, but we document updates and corrections to their data processing pipelines. The release is cumulative; it also includes the most recent reductions and calibrations of all data taken by SDSS since first light. In this paper we describe the location and format of the data and tools and cite technical references describing how it was obtained and processed. The SDSS website (www.sdss.org) has also been updated, providing links to data downloads, tutorials and examples of data use. While SDSS-IV will continue to collect astronomical data until 2020, and will be followed by SDSS-V (2020-2025), we end this paper by describing plans to ensure the sustainability of the SDSS data archive for many years beyond the collection of data. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1812.02759v2-abstract-full').style.display = 'none'; document.getElementById('1812.02759v2-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 December, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 6 December, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 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">Paper to accompany DR15. 25 pages, 6 figures. Accepted for publication in ApJSS. The two papers on the MaNGA Data Analysis Pipeline (DAP, Westfall et al. and Belfiore et al., see Section 4.1.2), and the paper on Marvin (Cherinka et al., see Section 4.2) have been submitted for collaboration review and will be posted to arXiv in due course. v2 fixes some broken URLs in the PDF</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1810.01525">arXiv:1810.01525</a> <span> [<a href="https://arxiv.org/pdf/1810.01525">pdf</a>, <a href="https://arxiv.org/ps/1810.01525">ps</a>, <a href="https://arxiv.org/format/1810.01525">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="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-3881/aae52d">10.3847/1538-3881/aae52d <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Project AMIGA: Distance and Metallicity Gradients Along Andromeda's Giant Southern Stream from the Red Clump </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Cohen%2C+R+E">Roger E. Cohen</a>, <a href="/search/?searchtype=author&query=Kalirai%2C+J+S">Jason S. Kalirai</a>, <a href="/search/?searchtype=author&query=Gilbert%2C+K+M">Karoline M. Gilbert</a>, <a href="/search/?searchtype=author&query=Guhathakurta%2C+P">Puragra Guhathakurta</a>, <a href="/search/?searchtype=author&query=Peeples%2C+M+S">Molly S. Peeples</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Brown%2C+T+M">Thomas M. Brown</a>, <a href="/search/?searchtype=author&query=Bianchi%2C+L">Luciana Bianchi</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=O%27Meara%2C+J+M">John M. O'Meara</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="1810.01525v1-abstract-short" style="display: inline;"> The Giant Southern Stream (GSS) of M31, a keystone signature of a major accretion event, yields crucial constraints on M31 formation and evolution models. Currently, our understanding of the GSS, in terms of both its geometry and its chemistry, results from either wide-field imaging probing only a few magnitudes below the red giant branch tip, or deep imaging or spectroscopy of isolated regions. H… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.01525v1-abstract-full').style.display = 'inline'; document.getElementById('1810.01525v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1810.01525v1-abstract-full" style="display: none;"> The Giant Southern Stream (GSS) of M31, a keystone signature of a major accretion event, yields crucial constraints on M31 formation and evolution models. Currently, our understanding of the GSS, in terms of both its geometry and its chemistry, results from either wide-field imaging probing only a few magnitudes below the red giant branch tip, or deep imaging or spectroscopy of isolated regions. Here, we take an alternative approach, using Hubble Space Telescope (HST) imaging to characterize the horizontal branch red clump (RC) using unbinned maximum likelihood fits to luminosity functions (LFs) from observed color-magnitude diagrams (CMDs). Comparing the RC mean magnitude across three fields at projected distances of 21, 52 and 80 kpc from M31, we find a line of sight distance gradient identical to recent literature measurements in fields along the core. We also find tentative evidence that the line of sight distance dispersion increases with projected distance from M31. Meanwhile, the metallicity in the 52 kpc field westward of the GSS core is at least as high as that in the 21 kpc GSS core field, and the peak colors of the RC in these two fields imply identical metallicities to within 0.2 dex. We discuss implications for distance and metallicity gradients both along and perpendicular to the GSS in the context of recent ground-based photometric and spectroscopic results, including evidence for a dropoff in metallicity moving westward from the GSS, as well as prospects for further constraining stellar populations in the vicinity of the GSS. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1810.01525v1-abstract-full').style.display = 'none'; document.getElementById('1810.01525v1-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 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">30 pages, 14 figures. AJ accepted. Figure quality has been reduced to meet arXiv size limits</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1808.09455">arXiv:1808.09455</a> <span> [<a href="https://arxiv.org/pdf/1808.09455">pdf</a>, <a href="https://arxiv.org/ps/1808.09455">ps</a>, <a href="https://arxiv.org/format/1808.09455">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/aadd0f">10.3847/1538-4357/aadd0f <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> New constraints on the nature and origin of the Leading Arm of the Magellanic Stream </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Richter%2C+P">P. Richter</a>, <a href="/search/?searchtype=author&query=Fox%2C+A+J">A. J. Fox</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">B. P. Wakker</a>, <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. C. Howk</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">N. Lehner</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=D%27Onghia%2C+E">E. D'Onghia</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">F. J. Lockman</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1808.09455v1-abstract-short" style="display: inline;"> We present a new precision measurement of gas-phase abundances of S, O, N, Si, Fe, P, Al, Ca as well as molecular hydrogen (H_2) in the Leading Arm (region II, LAII) of the Magellanic Stream (MS) towards the Seyfert galaxy NGC 3783. The results are based on high-quality archival ultraviolet/optical/radio data from various different instruments (HST/STIS, FUSE, AAT, GBT, GB140ft, ATCA). Our study u… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.09455v1-abstract-full').style.display = 'inline'; document.getElementById('1808.09455v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1808.09455v1-abstract-full" style="display: none;"> We present a new precision measurement of gas-phase abundances of S, O, N, Si, Fe, P, Al, Ca as well as molecular hydrogen (H_2) in the Leading Arm (region II, LAII) of the Magellanic Stream (MS) towards the Seyfert galaxy NGC 3783. The results are based on high-quality archival ultraviolet/optical/radio data from various different instruments (HST/STIS, FUSE, AAT, GBT, GB140ft, ATCA). Our study updates previous results from lower-resolution data and provides for the first time a self-consistent component model of the complex multi-phase absorber, delivering important constraints on the nature and origin of LAII. We derive a uniform, moderate alpha abundance in the two main absorber groups at +245 and +190 km s^-1 of alpha/H = 0.30 pm 0.05 solar, a low nitrogen abundance of N/H = 0.05 pm 0.01 solar, and a high dust content with substantial dust depletion values for Si, Fe, Al, and Ca. These alpha, N, and dust abundances in LAII are similar to those observed in the Small Magellanic Cloud (SMC). From the analysis of the H_2 absorption, we determine a high thermal pressure of P/k = 1680 K cm^-3 in LAII, in line with the idea that LAII is located in the inner Milky Way halo at a z-height of <20 kpc where it hydrodynamically interacts with the ambient hot coronal gas. Our study supports a scenario, in which LAII stems from the break-up of a metal- and dust-enriched progenitor cloud that was recently (200-500 Myr ago) stripped from the SMC. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1808.09455v1-abstract-full').style.display = 'none'; document.getElementById('1808.09455v1-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 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">18 pages, 12 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/1801.06446">arXiv:1801.06446</a> <span> [<a href="https://arxiv.org/pdf/1801.06446">pdf</a>, <a href="https://arxiv.org/ps/1801.06446">ps</a>, <a href="https://arxiv.org/format/1801.06446">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/aaa9bb">10.3847/1538-4357/aaa9bb <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Chemical Abundances in the Leading Arm of the Magellanic Stream </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Richter%2C+P">Philipp Richter</a>, <a href="/search/?searchtype=author&query=Antwi-Danso%2C+J">Jacqueline Antwi-Danso</a>, <a href="/search/?searchtype=author&query=Casetti-Dinescu%2C+D+I">Dana I. Casetti-Dinescu</a>, <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. Christopher Howk</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=D%27Onghia%2C+E">Elena D'Onghia</a>, <a href="/search/?searchtype=author&query=Crowther%2C+P+A">Paul A. Crowther</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">Felix J. Lockman</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="1801.06446v1-abstract-short" style="display: inline;"> The Leading Arm (LA) of the Magellanic Stream is a vast debris field of H I clouds connecting the Milky Way and the Magellanic Clouds. It represents an example of active gas accretion onto the Galaxy. Previously only one chemical abundance measurement had been made in the LA. Here we present chemical abundance measurements using Hubble Space Telescope/Cosmic Origins Spectrograph Green Bank Telesco… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.06446v1-abstract-full').style.display = 'inline'; document.getElementById('1801.06446v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1801.06446v1-abstract-full" style="display: none;"> The Leading Arm (LA) of the Magellanic Stream is a vast debris field of H I clouds connecting the Milky Way and the Magellanic Clouds. It represents an example of active gas accretion onto the Galaxy. Previously only one chemical abundance measurement had been made in the LA. Here we present chemical abundance measurements using Hubble Space Telescope/Cosmic Origins Spectrograph Green Bank Telescope spectra of four sightlines passing through the LA, and three nearby sightlines that may trace outer fragments of the LA. We find low oxygen abundances, ranging from 4.0(+4.0,-2.0) percent solar to 12.6(+6.2,-4.1) percent solar, in the confirmed LA directions, with the lowest values found in the region known as LA III, farthest from the LMC. These abundances are substantially lower than the single previous measurement, S/H=35+/-7 percent solar (Lu et al. 1998), but are in agreement with those reported in the SMC filament of the trailing Stream, supporting a common origin in the SMC (not the LMC) for the majority of the LA and the trailing Stream. This provides important constraints for models of the formation of the Magellanic System. Finally, the HVCs in two of the three nearby sightlines show H I columns, kinematics, and oxygen abundances consistent with LA membership. This suggests that the LA is larger than traditionally thought, extending at least 20 degrees further to the Galactic northwest. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1801.06446v1-abstract-full').style.display = 'none'; document.getElementById('1801.06446v1-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 January, 2018; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> January 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 ApJ, 14 pages, 3 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/1711.04395">arXiv:1711.04395</a> <span> [<a href="https://arxiv.org/pdf/1711.04395">pdf</a>, <a href="https://arxiv.org/format/1711.04395">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/aa992a">10.3847/1538-4357/aa992a <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Revealing the Ionization Properties of the Magellanic Stream using Optical Emission </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=Madsen%2C+G+J">G. J. Madsen</a>, <a href="/search/?searchtype=author&query=Fox%2C+A+J">A. J. Fox</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">B. P. Wakker</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">J. Bland-Hawthorn</a>, <a href="/search/?searchtype=author&query=Nidever%2C+D">D. Nidever</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. M. Haffner</a>, <a href="/search/?searchtype=author&query=Antwi-Danso%2C+J">J. Antwi-Danso</a>, <a href="/search/?searchtype=author&query=Hernandez%2C+M">M. Hernandez</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">N. Lehner</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">A. S. Hill</a>, <a href="/search/?searchtype=author&query=Curzons%2C+A">A. Curzons</a>, <a href="/search/?searchtype=author&query=Tepper-Garcia%2C+T">T. Tepper-Garcia</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="1711.04395v1-abstract-short" style="display: inline;"> The Magellanic Stream, a gaseous tail that trails behind the Magellanic Clouds, could replenish the Milky Way with a tremendous amount of gas if it reaches the Galactic disk before it evaporates into the halo. To determine how the Magellanic Stream's properties change along its length, we have conducted an observational study of the H-alpha emission, along with other optical warm ionized gas trace… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.04395v1-abstract-full').style.display = 'inline'; document.getElementById('1711.04395v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1711.04395v1-abstract-full" style="display: none;"> The Magellanic Stream, a gaseous tail that trails behind the Magellanic Clouds, could replenish the Milky Way with a tremendous amount of gas if it reaches the Galactic disk before it evaporates into the halo. To determine how the Magellanic Stream's properties change along its length, we have conducted an observational study of the H-alpha emission, along with other optical warm ionized gas tracers, toward 39 sight lines. Using the Wisconsin H-alpha Mapper telescope, we detect H-alpha emission brighter than 30 - 50 mR in 26 of our 39 sight lines. This H-alpha emission extends more than 2-degree away from the HI emission. By comparing H-alpha and [OI] intensities, we find that regions with log NHI = 19.5 - 20.0 are 16 - 67% ionized. Most of the H-alpha intensities along the Magellanic Stream are much higher than expected if the primary ionization source is photoionization from Magellanic Clouds, the Milky Way, and the extragalactic background. We find that the additional contribution from self ionization through a "shock cascade" that results as the Stream plows through the halo might be sufficient to reproduce the underlying level of H-alpha emission along the Stream. In the sparsely sampled region below the South Galactic Pole, there exists a subset of sight lines with uncharacteristically bright emission, which suggest that gas is being ionized further by an additional source that could be a linked to energetic processes associated with the Galactic center. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1711.04395v1-abstract-full').style.display = 'none'; document.getElementById('1711.04395v1-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 November, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in the Astrophysical Journal on Nov 8, 2017</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1707.09322">arXiv:1707.09322</a> <span> [<a href="https://arxiv.org/pdf/1707.09322">pdf</a>, <a href="https://arxiv.org/format/1707.09322">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 class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.3847/1538-4365/aa9e8a">10.3847/1538-4365/aa9e8a <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Abolfathi%2C+B">Bela Abolfathi</a>, <a href="/search/?searchtype=author&query=Aguado%2C+D+S">D. S. Aguado</a>, <a href="/search/?searchtype=author&query=Aguilar%2C+G">Gabriela Aguilar</a>, <a href="/search/?searchtype=author&query=Prieto%2C+C+A">Carlos Allende Prieto</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Ananna%2C+T+T">Tonima Tasnim Ananna</a>, <a href="/search/?searchtype=author&query=Anders%2C+F">Friedrich Anders</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B+H">Brett H. Andrews</a>, <a href="/search/?searchtype=author&query=Anguiano%2C+B">Borja Anguiano</a>, <a href="/search/?searchtype=author&query=Aragon-Salamanca%2C+A">Alfonso Aragon-Salamanca</a>, <a href="/search/?searchtype=author&query=Argudo-Fernandez%2C+M">Maria Argudo-Fernandez</a>, <a href="/search/?searchtype=author&query=Armengaud%2C+E">Eric Armengaud</a>, <a href="/search/?searchtype=author&query=Ata%2C+M">Metin Ata</a>, <a href="/search/?searchtype=author&query=Aubourg%2C+E">Eric Aubourg</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Bailey%2C+S">Stephen Bailey</a>, <a href="/search/?searchtype=author&query=Balland%2C+C">Christophe Balland</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J">Jorge Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Bartosz%2C+C">Curtis Bartosz</a>, <a href="/search/?searchtype=author&query=Bastien%2C+F">Fabienne Bastien</a>, <a href="/search/?searchtype=author&query=Bates%2C+D">Dominic Bates</a>, <a href="/search/?searchtype=author&query=Baumgarten%2C+F">Falk Baumgarten</a> , et al. (323 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="1707.09322v3-abstract-short" style="display: inline;"> The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulativ… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.09322v3-abstract-full').style.display = 'inline'; document.getElementById('1707.09322v3-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1707.09322v3-abstract-full" style="display: none;"> The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1707.09322v3-abstract-full').style.display = 'none'; document.getElementById('1707.09322v3-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, 2018; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 28 July, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected)</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1706.01893">arXiv:1706.01893</a> <span> [<a href="https://arxiv.org/pdf/1706.01893">pdf</a>, <a href="https://arxiv.org/format/1706.01893">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/aa87b4">10.3847/1538-4357/aa87b4 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Project AMIGA: A Minimal Covering Factor for Optically Thick Circumgalactic Gas Around the Andromeda Galaxy </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. Christopher Howk</a>, <a href="/search/?searchtype=author&query=Wotta%2C+C+B">Christopher B. Wotta</a>, <a href="/search/?searchtype=author&query=Berg%2C+M+A">Michelle A. Berg</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">Felix J. Lockman</a>, <a href="/search/?searchtype=author&query=Hafen%2C+Z">Zachary Hafen</a>, <a href="/search/?searchtype=author&query=Pisano%2C+D+J">D. J. Pisano</a>, <a href="/search/?searchtype=author&query=Faucher-Giguere%2C+C">Claude-Andre Faucher-Giguere</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Prochaska%2C+J+X">J. Xavier Prochaska</a>, <a href="/search/?searchtype=author&query=Wolfe%2C+S+A">Spencer A. Wolfe</a>, <a href="/search/?searchtype=author&query=Ribaudo%2C+J">Joseph Ribaudo</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Corlies%2C+L">Lauren Corlies</a>, <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Guhathakurta%2C+P">Puragra Guhathakurta</a>, <a href="/search/?searchtype=author&query=Jenkins%2C+E+B">Edward B. Jenkins</a>, <a href="/search/?searchtype=author&query=Kalirai%2C+J">Jason Kalirai</a>, <a href="/search/?searchtype=author&query=O%27Meara%2C+J+M">John M. O'Meara</a>, <a href="/search/?searchtype=author&query=Peeples%2C+M+S">Molly S. Peeples</a>, <a href="/search/?searchtype=author&query=Stewart%2C+K+R">Kyle R. Stewart</a>, <a href="/search/?searchtype=author&query=Strader%2C+J">Jay Strader</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1706.01893v2-abstract-short" style="display: inline;"> We present a deep search for HI 21-cm emission from the gaseous halo of Messier 31 as part of Project AMIGA, a large program Hubble Space Telescope program to study the circumgalactic medium of the Andromeda galaxy. Our observations with the Robert C. Byrd Green Bank Telesope target sight lines to 48 background AGNs, more than half of which have been observed in the ultraviolet with the Cosmic Ori… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.01893v2-abstract-full').style.display = 'inline'; document.getElementById('1706.01893v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1706.01893v2-abstract-full" style="display: none;"> We present a deep search for HI 21-cm emission from the gaseous halo of Messier 31 as part of Project AMIGA, a large program Hubble Space Telescope program to study the circumgalactic medium of the Andromeda galaxy. Our observations with the Robert C. Byrd Green Bank Telesope target sight lines to 48 background AGNs, more than half of which have been observed in the ultraviolet with the Cosmic Origins Spectrograph, with impact parameters $25 \lesssim 蟻\lesssim 330$ kpc ($0.1 \lesssim 蟻/ R_{\rm vir} \lesssim 1.1$). We do not detect any 21-cm emission toward these AGNs to limits of $N({\rm HI}) \approx 4 \times10^{17}$ cm$^{-2}$ ($5蟽$, per 2 kpc diameter beam). This column density corresponds to an optical depth of $\sim2.5$ at the Lyman limit, thus our observations overlap with absorption line studies of Lyman limit systems at higher redshift. Our non-detections place a limit on the covering factor of such optically-thick gas around M31 to $f_c < 0.051$ (at 90\% confidence) for $蟻\leq R_{\rm vir}$. While individual clouds have previously been found in the region between M31 and M33, the covering factor of strongly optically-thick gas is quite small. Our upper limits on the covering factor are consistent with expectations from recent cosmological "zoom" simulations. Recent COS-Halos ultraviolet measurements of \HI\ absorption about an ensemble of galaxies at $z \approx 0.2$ show significantly higher covering factors within $蟻\lesssim 0.5 R_{\rm vir}$ at the same $N({\rm H I})$, although the metal ion-to-H I ratios appear to be consistent with those seen in M31. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1706.01893v2-abstract-full').style.display = 'none'; document.getElementById('1706.01893v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 August, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 6 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in the ApJ. GBT data and paper products available through https://github.com/jchowk/AMIGA-GBT2017</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1703.00052">arXiv:1703.00052</a> <span> [<a href="https://arxiv.org/pdf/1703.00052">pdf</a>, <a href="https://arxiv.org/format/1703.00052">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/aa7567">10.3847/1538-3881/aa7567 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Sloan Digital Sky Survey IV: Mapping the Milky Way, Nearby Galaxies, and the Distant Universe </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Blanton%2C+M+R">Michael R. Blanton</a>, <a href="/search/?searchtype=author&query=Bershady%2C+M+A">Matthew A. Bershady</a>, <a href="/search/?searchtype=author&query=Abolfathi%2C+B">Bela Abolfathi</a>, <a href="/search/?searchtype=author&query=Albareti%2C+F+D">Franco D. Albareti</a>, <a href="/search/?searchtype=author&query=Prieto%2C+C+A">Carlos Allende Prieto</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Alonso-Garc%C3%ADa%2C+J">Javier Alonso-Garc铆a</a>, <a href="/search/?searchtype=author&query=Anders%2C+F">Friedrich Anders</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S+F">Scott F. Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B">Brett Andrews</a>, <a href="/search/?searchtype=author&query=Aquino-Ort%C3%ADz%2C+E">Erik Aquino-Ort铆z</a>, <a href="/search/?searchtype=author&query=Arag%C3%B3n-Salamanca%2C+A">Alfonso Arag贸n-Salamanca</a>, <a href="/search/?searchtype=author&query=Argudo-Fern%C3%A1ndez%2C+M">Maria Argudo-Fern谩ndez</a>, <a href="/search/?searchtype=author&query=Armengaud%2C+E">Eric Armengaud</a>, <a href="/search/?searchtype=author&query=Aubourg%2C+E">Eric Aubourg</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Bailey%2C+S">Stephen Bailey</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J">Jorge Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Bartosz%2C+C">Curtis Bartosz</a>, <a href="/search/?searchtype=author&query=Bates%2C+D">Dominic Bates</a>, <a href="/search/?searchtype=author&query=Baumgarten%2C+F">Falk Baumgarten</a>, <a href="/search/?searchtype=author&query=Bautista%2C+J">Julian Bautista</a>, <a href="/search/?searchtype=author&query=Beaton%2C+R">Rachael Beaton</a> , et al. (328 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="1703.00052v2-abstract-short" style="display: inline;"> We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratio in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spat… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1703.00052v2-abstract-full').style.display = 'inline'; document.getElementById('1703.00052v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1703.00052v2-abstract-full" style="display: none;"> We describe the Sloan Digital Sky Survey IV (SDSS-IV), a project encompassing three major spectroscopic programs. The Apache Point Observatory Galactic Evolution Experiment 2 (APOGEE-2) is observing hundreds of thousands of Milky Way stars at high resolution and high signal-to-noise ratio in the near-infrared. The Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey is obtaining spatially-resolved spectroscopy for thousands of nearby galaxies (median redshift of z = 0.03). The extended Baryon Oscillation Spectroscopic Survey (eBOSS) is mapping the galaxy, quasar, and neutral gas distributions between redshifts z = 0.6 and 3.5 to constrain cosmology using baryon acoustic oscillations, redshift space distortions, and the shape of the power spectrum. Within eBOSS, we are conducting two major subprograms: the SPectroscopic IDentification of eROSITA Sources (SPIDERS), investigating X-ray AGN and galaxies in X-ray clusters, and the Time Domain Spectroscopic Survey (TDSS), obtaining spectra of variable sources. All programs use the 2.5-meter Sloan Foundation Telescope at Apache Point Observatory; observations there began in Summer 2014. APOGEE-2 also operates a second near-infrared spectrograph at the 2.5-meter du Pont Telescope at Las Campanas Observatory, with observations beginning in early 2017. Observations at both facilities are scheduled to continue through 2020. In keeping with previous SDSS policy, SDSS-IV provides regularly scheduled public data releases; the first one, Data Release 13, was made available in July 2016. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1703.00052v2-abstract-full').style.display = 'none'; document.getElementById('1703.00052v2-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 June, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 28 February, 2017; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2017. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Published in Astronomical Journal</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> The Astronomical Journal, Volume 154, Number 1, pp. 28-62 (2017) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1610.08785">arXiv:1610.08785</a> <span> [<a href="https://arxiv.org/pdf/1610.08785">pdf</a>, <a href="https://arxiv.org/format/1610.08785">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/aa63e6">10.3847/1538-4357/aa63e6 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Warm Ionized Medium Throughout the Sagittarius-Carina Arm </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Krishnarao%2C+D">Dhanesh Krishnarao</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. Matthew Haffner</a>, <a href="/search/?searchtype=author&query=Benjamin%2C+R+A">Robert A. Benjamin</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">Alex S. Hill</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</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="1610.08785v2-abstract-short" style="display: inline;"> Wisconsin H-Alpha Mapper (WHAM) observations of H-Alpha and [S II]$\lambda6716$ emission are used to trace the vertical distribution and physical conditions of the warm ionized medium (WIM) along the Sagittarius-Carina arm. CO emission, tracing cold molecular gas in the plane of the Galaxy, is used as a guide to isolate H-Alpha and [S II] emission along individual spiral arms. Exponential scale he… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1610.08785v2-abstract-full').style.display = 'inline'; document.getElementById('1610.08785v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1610.08785v2-abstract-full" style="display: none;"> Wisconsin H-Alpha Mapper (WHAM) observations of H-Alpha and [S II]$\lambda6716$ emission are used to trace the vertical distribution and physical conditions of the warm ionized medium (WIM) along the Sagittarius-Carina arm. CO emission, tracing cold molecular gas in the plane of the Galaxy, is used as a guide to isolate H-Alpha and [S II] emission along individual spiral arms. Exponential scale heights of electron density squared (or emission measure) are determined using H-Alpha emission above (below) the midplane to be $330 \pm 80$ pc ( $550 \pm 230$ pc) along the near Sagittarius arm, $300 \pm 100$ pc ($250 \pm 30$ pc) along the near Carina arm, and $>1000$ pc along the far Carina arm. The emission measure scale height tends to increase as a function of Galactocentric radius along the Sagittarius-Carina arm for $R_G > 8$ kpc. Physical conditions of the ionized gas are analyzed using the [S II]/H-Alpha line ratio, which more closely traces H-Alpha Intensity than height above the plane, z, suggesting a stronger relationship with the in-situ electron density. We interpret this result as further evidence for the majority of the observed diffuse emission originating from in-situ ionized gas as opposed to scattered light from classical H II regions in the plane. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1610.08785v2-abstract-full').style.display = 'none'; document.getElementById('1610.08785v2-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 February, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 27 October, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2016. </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, 19 figures, 2 tables, 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/1608.02013">arXiv:1608.02013</a> <span> [<a href="https://arxiv.org/pdf/1608.02013">pdf</a>, <a href="https://arxiv.org/format/1608.02013">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/10.3847/1538-4365/aa8992">10.3847/1538-4365/aa8992 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Thirteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-IV Survey MApping Nearby Galaxies at Apache Point Observatory </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=SDSS+Collaboration"> SDSS Collaboration</a>, <a href="/search/?searchtype=author&query=Albareti%2C+F+D">Franco D. Albareti</a>, <a href="/search/?searchtype=author&query=Prieto%2C+C+A">Carlos Allende Prieto</a>, <a href="/search/?searchtype=author&query=Almeida%2C+A">Andres Almeida</a>, <a href="/search/?searchtype=author&query=Anders%2C+F">Friedrich Anders</a>, <a href="/search/?searchtype=author&query=Anderson%2C+S">Scott Anderson</a>, <a href="/search/?searchtype=author&query=Andrews%2C+B+H">Brett H. Andrews</a>, <a href="/search/?searchtype=author&query=Aragon-Salamanca%2C+A">Alfonso Aragon-Salamanca</a>, <a href="/search/?searchtype=author&query=Argudo-Fernandez%2C+M">Maria Argudo-Fernandez</a>, <a href="/search/?searchtype=author&query=Armengaud%2C+E">Eric Armengaud</a>, <a href="/search/?searchtype=author&query=Aubourg%2C+E">Eric Aubourg</a>, <a href="/search/?searchtype=author&query=Avila-Reese%2C+V">Vladimir Avila-Reese</a>, <a href="/search/?searchtype=author&query=Badenes%2C+C">Carles Badenes</a>, <a href="/search/?searchtype=author&query=Bailey%2C+S">Stephen Bailey</a>, <a href="/search/?searchtype=author&query=Barbuy%2C+B">Beatriz Barbuy</a>, <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Barrera-Ballesteros%2C+J">Jorge Barrera-Ballesteros</a>, <a href="/search/?searchtype=author&query=Bartosz%2C+C">Curtis Bartosz</a>, <a href="/search/?searchtype=author&query=Basu%2C+S">Sarbani Basu</a>, <a href="/search/?searchtype=author&query=Bates%2C+D">Dominic Bates</a>, <a href="/search/?searchtype=author&query=Battaglia%2C+G">Giuseppina Battaglia</a>, <a href="/search/?searchtype=author&query=Baumgarten%2C+F">Falk Baumgarten</a>, <a href="/search/?searchtype=author&query=Baur%2C+J">Julien Baur</a>, <a href="/search/?searchtype=author&query=Bautista%2C+J">Julian Bautista</a>, <a href="/search/?searchtype=author&query=Beers%2C+T+C">Timothy C. Beers</a> , et al. (314 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="1608.02013v2-abstract-short" style="display: inline;"> The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2, MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.02013v2-abstract-full').style.display = 'inline'; document.getElementById('1608.02013v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1608.02013v2-abstract-full" style="display: none;"> The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) began observations in July 2014. It pursues three core programs: APOGEE-2, MaNGA, and eBOSS. In addition, eBOSS contains two major subprograms: TDSS and SPIDERS. This paper describes the first data release from SDSS-IV, Data Release 13 (DR13), which contains new data, reanalysis of existing data sets and, like all SDSS data releases, is inclusive of previously released data. DR13 makes publicly available 1390 spatially resolved integral field unit observations of nearby galaxies from MaNGA, the first data released from this survey. It includes new observations from eBOSS, completing SEQUELS. In addition to targeting galaxies and quasars, SEQUELS also targeted variability-selected objects from TDSS and X-ray selected objects from SPIDERS. DR13 includes new reductions of the SDSS-III BOSS data, improving the spectrophotometric calibration and redshift classification. DR13 releases new reductions of the APOGEE-1 data from SDSS-III, with abundances of elements not previously included and improved stellar parameters for dwarf stars and cooler stars. For the SDSS imaging data, DR13 provides new, more robust and precise photometric calibrations. Several value-added catalogs are being released in tandem with DR13, in particular target catalogs relevant for eBOSS, TDSS, and SPIDERS, and an updated red-clump catalog for APOGEE. This paper describes the location and format of the data now publicly available, as well as providing references to the important technical papers that describe the targeting, observing, and data reduction. The SDSS website, http://www.sdss.org, provides links to the data, tutorials and examples of data access, and extensive documentation of the reduction and analysis procedures. DR13 is the first of a scheduled set that will contain new data and analyses from the planned ~6-year operations of SDSS-IV. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1608.02013v2-abstract-full').style.display = 'none'; document.getElementById('1608.02013v2-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, 2017; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 5 August, 2016; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2016. </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">Full information on DR13 available at http://www.sdss.org. Comments welcome to spokesperson@sdss.org. To be published in ApJS</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1512.04957">arXiv:1512.04957</a> <span> [<a href="https://arxiv.org/pdf/1512.04957">pdf</a>, <a href="https://arxiv.org/ps/1512.04957">ps</a>, <a href="https://arxiv.org/format/1512.04957">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/10.3847/2041-8205/816/1/L11">10.3847/2041-8205/816/1/L11 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> On the Metallicity and Origin of the Smith High-Velocity Cloud </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Lockman%2C+F+J">Felix J. Lockman</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">Alex S. Hill</a>, <a href="/search/?searchtype=author&query=Heitsch%2C+F">Fabian Heitsch</a>, <a href="/search/?searchtype=author&query=Stark%2C+D+V">David V. Stark</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Sembach%2C+K+R">Kenneth R. Sembach</a>, <a href="/search/?searchtype=author&query=Rahman%2C+M">Mubdi Rahman</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="1512.04957v1-abstract-short" style="display: inline;"> The Smith Cloud is a gaseous high-velocity cloud (HVC) in an advanced state of accretion, only 2.9 kpc below the Galactic plane and due to impact the disk in 27 Myr. It is unique among HVCs in having a known distance (12.4+/-1.3 kpc) and a well-constrained 3D velocity (296 km/s), but its origin has long remained a mystery. Here we present the first absorption-line measurements of its metallicity,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1512.04957v1-abstract-full').style.display = 'inline'; document.getElementById('1512.04957v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1512.04957v1-abstract-full" style="display: none;"> The Smith Cloud is a gaseous high-velocity cloud (HVC) in an advanced state of accretion, only 2.9 kpc below the Galactic plane and due to impact the disk in 27 Myr. It is unique among HVCs in having a known distance (12.4+/-1.3 kpc) and a well-constrained 3D velocity (296 km/s), but its origin has long remained a mystery. Here we present the first absorption-line measurements of its metallicity, using HST/COS UV spectra of three AGN lying behind the Cloud together with Green Bank Telescope 21 cm spectra of the same directions. Using Voigt-profile fitting of the S II 1250, 1253, 1259 triplet together with ionization corrections derived from photoionization modeling, we derive the sulfur abundance in each direction; a weighted average of the three measurements gives [S/H]=-0.28+/-0.14, or 0.53+0.21-0.15 solar metallicity. The finding that the Smith Cloud is metal-enriched lends support to scenarios where it represents recycled Galactic material rather than the remnant of a dwarf galaxy or accreting intergalactic gas. The metallicity and trajectory of the Cloud are both indicative of an origin in the outer disk. However, its large mass and prograde kinematics remain to be fully explained. If the cloud has accreted cooling gas from the corona during its fountain trajectory, as predicted in recent theoretical work, its current mass would be higher than its launch mass, alleviating the mass concern. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1512.04957v1-abstract-full').style.display = 'none'; document.getElementById('1512.04957v1-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 December, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2015. </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 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/1512.00461">arXiv:1512.00461</a> <span> [<a href="https://arxiv.org/pdf/1512.00461">pdf</a>, <a href="https://arxiv.org/format/1512.00461">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/10.3847/0004-637X/817/2/91">10.3847/0004-637X/817/2/91 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Down-the-barrel and transverse observations of the Large Magellanic Cloud: evidence for a symmetrical galactic wind on the near and far sides of the galaxy </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K">Kat Barger</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. Chris Howk</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="1512.00461v1-abstract-short" style="display: inline;"> We compare the properties of gas flows on both the near and far side of the Large Magellanic Cloud (LMC) disk using Hubble Space Telescope UV absorption-line observations toward an AGN behind (transverse) and a star within (down-the-barrel) the LMC disk at an impact parameter of 3.2 kpc. We find that even in this relatively quiescent region gas flows away from the disk at speeds up to $\sim$100 km… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1512.00461v1-abstract-full').style.display = 'inline'; document.getElementById('1512.00461v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1512.00461v1-abstract-full" style="display: none;"> We compare the properties of gas flows on both the near and far side of the Large Magellanic Cloud (LMC) disk using Hubble Space Telescope UV absorption-line observations toward an AGN behind (transverse) and a star within (down-the-barrel) the LMC disk at an impact parameter of 3.2 kpc. We find that even in this relatively quiescent region gas flows away from the disk at speeds up to $\sim$100 km/s in broad and symmetrical absorption in the low and high ions. The symmetric absorption profiles combined with previous surveys showing little evidence that the ejected gas returns to the LMC and provide compelling evidence that the LMC drives a global, large-scale outflow across its disk, which is the likely result of a recent burst of star formation in the LMC. We find that the outflowing gas is multiphase, ionized by both photoionization (SiII and SiIII) and collisional ionization (SiIV and CIV). We estimate a total mass and outflow rate to be $>10^7$ Msun and $>0.4$ Msun/yr. Since the velocity of this large-scale outflow does not reach the LMC escape velocity, the gas removal is likely aided by either ram-pressure stripping with the Milky Way halo or tidal interactions with the surrounding galaxies, implying that the environment of LMC-like or dwarf galaxies plays an important role in their ultimate gas starvation. Finally we reassess the mass and plausible origins of the high-velocity complex toward the LMC given its newly-determined distance that places it in the lower Milky Way halo and sky-coverage that shows it extends well beyond the LMC disk. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1512.00461v1-abstract-full').style.display = 'none'; document.getElementById('1512.00461v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 1 December, 2015; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2015. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted to ApJ</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1404.5514">arXiv:1404.5514</a> <span> [<a href="https://arxiv.org/pdf/1404.5514">pdf</a>, <a href="https://arxiv.org/ps/1404.5514">ps</a>, <a href="https://arxiv.org/format/1404.5514">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/10.1088/0004-637X/787/2/147">10.1088/0004-637X/787/2/147 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The COS/UVES Absorption Survey of the Magellanic Stream. III: Ionization, Total Mass, and Inflow Rate onto the Milky Way </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Fox%2C+A+J">Andrew J. Fox</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Hernandez%2C+A+K">Audra K. Hernandez</a>, <a href="/search/?searchtype=author&query=Richter%2C+P">Philipp Richter</a>, <a href="/search/?searchtype=author&query=Lehner%2C+N">Nicolas Lehner</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">Joss Bland-Hawthorn</a>, <a href="/search/?searchtype=author&query=Charlton%2C+J+C">Jane C. Charlton</a>, <a href="/search/?searchtype=author&query=Westmeier%2C+T">Tobias Westmeier</a>, <a href="/search/?searchtype=author&query=Thom%2C+C">Christopher Thom</a>, <a href="/search/?searchtype=author&query=Tumlinson%2C+J">Jason Tumlinson</a>, <a href="/search/?searchtype=author&query=Misawa%2C+T">Toru Misawa</a>, <a href="/search/?searchtype=author&query=Howk%2C+J+C">J. Christopher Howk</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. Matthew Haffner</a>, <a href="/search/?searchtype=author&query=Ely%2C+J">Justin Ely</a>, <a href="/search/?searchtype=author&query=Rodriguez-Hidalgo%2C+P">Paola Rodriguez-Hidalgo</a>, <a href="/search/?searchtype=author&query=Kumari%2C+N">Nimisha Kumari</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="1404.5514v1-abstract-short" style="display: inline;"> Dynamic interactions between the two Magellanic Clouds have flung large quantities of gas into the halo of the Milky Way, creating the Magellanic Stream, the Magellanic Bridge, and the Leading Arm (collectively referred to as the Magellanic System). In this third paper of a series studying the Magellanic gas in absorption, we analyze the gas ionization level using a sample of 69 Hubble Space Teles… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.5514v1-abstract-full').style.display = 'inline'; document.getElementById('1404.5514v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1404.5514v1-abstract-full" style="display: none;"> Dynamic interactions between the two Magellanic Clouds have flung large quantities of gas into the halo of the Milky Way, creating the Magellanic Stream, the Magellanic Bridge, and the Leading Arm (collectively referred to as the Magellanic System). In this third paper of a series studying the Magellanic gas in absorption, we analyze the gas ionization level using a sample of 69 Hubble Space Telescope/Cosmic Origins Spectrograph sightlines that pass through or within 30 degrees of the 21 cm-emitting regions. We find that 81% (56/69) of the sightlines show UV absorption at Magellanic velocities, indicating that the total cross section of the Magellanic System is ~11 000 square degrees, or around a quarter of the entire sky. Using observations of the Si III/Si II ratio together with Cloudy photoionization modeling, we calculate that the total mass (atomic plus ionized) of the Magellanic System is ~2.0 billion solar masses, with the ionized gas contributing over twice as much mass as the atomic gas. This is larger than the current-day interstellar H I mass of both Magellanic Clouds combined, indicating that they have lost most of their initial gas mass. If the gas in the Magellanic System survives to reach the Galactic disk over its inflow time of ~0.5-1.5 Gyr, it will represent an average inflow rate of ~3.7-6.7 solar masses per year, potentially raising the Galactic star formation rate. However, multiple signs of an evaporative interaction with the hot Galactic corona indicate that the Stream may not survive its journey to the disk fully intact, and will instead add material to (and cool) the corona. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.5514v1-abstract-full').style.display = 'none'; document.getElementById('1404.5514v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 22 April, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in ApJ, 32 pages, 7 figures, 3 tables, Figure 1 shown at low resolution to reduce file size</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1404.1930">arXiv:1404.1930</a> <span> [<a href="https://arxiv.org/pdf/1404.1930">pdf</a>, <a href="https://arxiv.org/format/1404.1930">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/10.1088/0004-637X/787/2/106">10.1088/0004-637X/787/2/106 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Halpha and [S II] emission from warm ionized gas in the Scutum-Centaurus Arm </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Hill%2C+A+S">Alex S. Hill</a>, <a href="/search/?searchtype=author&query=Benjamin%2C+R+A">Robert A. Benjamin</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. Matthew Haffner</a>, <a href="/search/?searchtype=author&query=Gostisha%2C+M">Martin Gostisha</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</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="1404.1930v1-abstract-short" style="display: inline;"> We present Wisconsin H-Alpha Mapper [S II] 位6716 and H伪 spectroscopic maps of the warm ionized medium (WIM) in the Scutum-Centaurus Arm at Galactic longitudes 310掳 < l < 345掳. Using extinction-corrected H伪 intensities (IH伪c), we measure an exponential scale height of electron density-squared in the arm of H_ne^2 = 0.30 kpc (assuming a distance of 3.5 kpc), intermediate between that observed in the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.1930v1-abstract-full').style.display = 'inline'; document.getElementById('1404.1930v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1404.1930v1-abstract-full" style="display: none;"> We present Wisconsin H-Alpha Mapper [S II] 位6716 and H伪 spectroscopic maps of the warm ionized medium (WIM) in the Scutum-Centaurus Arm at Galactic longitudes 310掳 < l < 345掳. Using extinction-corrected H伪 intensities (IH伪c), we measure an exponential scale height of electron density-squared in the arm of H_ne^2 = 0.30 kpc (assuming a distance of 3.5 kpc), intermediate between that observed in the inner Galaxy and in the Perseus Arm. The [S II]/H伪 line ratio is enhanced at large |z| and in sightlines with faint IH伪c. We find that the [S II]/H伪 line ratio has a power law relationship with IH伪c from a value of ~=1.0 at IH伪c < 0.2 R (Rayleighs) to a value of ~=0.08 at IH伪c >= 100 R. The line ratio is better correlated with H伪 intensity than with height above the plane, indicating that the physical conditions within the WIM vary systematically with electron density. We argue that the variation of the line ratio with height is a consequence of the decrease of electron density with height. Our results reinforce the well-established picture in which the diffuse H伪 emission is due primarily to emission from in situ photoionized gas, with scattered light only a minor contributor. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1404.1930v1-abstract-full').style.display = 'none'; document.getElementById('1404.1930v1-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 April, 2014; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2014. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">ApJ in press. 8 pages in emulateapj format</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> 2014 ApJ 787:106 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1305.4932">arXiv:1305.4932</a> <span> [<a href="https://arxiv.org/pdf/1305.4932">pdf</a>, <a href="https://arxiv.org/ps/1305.4932">ps</a>, <a href="https://arxiv.org/format/1305.4932">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/10.1088/0004-637X/771/2/132">10.1088/0004-637X/771/2/132 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Warm Ionized Gas Revealed in the Magellanic Bridge Tidal Remnant: Constraining the Baryon Content and the Escaping Ionizing Photons around Dwarf Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. M. Haffner</a>, <a href="/search/?searchtype=author&query=Bland-Hawthorn%2C+J">J. Bland-Hawthorn</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="1305.4932v2-abstract-short" style="display: inline;"> The Magellanic System includes some of the nearest examples of galaxies disturbed by galaxy interactions. These interactions have redistributed much of their gas into the halos of the Milky Way and the Magellanic Clouds. We present Wisconsin H-alpha Mapper kinematically resolved observations of the warm ionized gas in the Magellanic Bridge over the velocity range of +100 to +300 km/s in the local… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.4932v2-abstract-full').style.display = 'inline'; document.getElementById('1305.4932v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1305.4932v2-abstract-full" style="display: none;"> The Magellanic System includes some of the nearest examples of galaxies disturbed by galaxy interactions. These interactions have redistributed much of their gas into the halos of the Milky Way and the Magellanic Clouds. We present Wisconsin H-alpha Mapper kinematically resolved observations of the warm ionized gas in the Magellanic Bridge over the velocity range of +100 to +300 km/s in the local standard-of-rest reference frame. These observations include the first full H-alpha intensity map and the corresponding intensity-weighted mean velocity map of the Magellanic Bridge across (l, b) = (281.5, -30.0) to (302.5, -46.7). Using the H-alpha emission from the SMC-Tail and the Bridge we estimate that the mass of the ionized material is between (0.7-1.7)x10^8 times the mass of the Sun, compared to 3.3x10^8 times the mass of the Sun for the neutral mass over the same region. The diffuse Bridge is significantly more ionized than the SMC-Tail, with an ionization fraction of 36-52% compared to 5-24% for the Tail. The H-alpha emission has a complex multiple-component structure with a velocity distribution that could trace the sources of ionization or distinct ionized structures. We find that incident radiation from the extragalactic background and the Milky Way alone are insufficient to produced the observed ionization in the Magellanic Bridge and present a model for the escape fraction of the ionizing photons from both the Small and Large Magellanic Clouds. With this model, we place an upper limit of 4.0% for the average escape fraction of ionizing photons from the LMC and an upper limit of 5.5% for the SMC. These results, combined with the findings of a half a dozen results for dwarf galaxies in different environments, provide compelling evidence that only a small percentage of the ionizing photons escape from dwarf galaxies in the present epoch to influence their surroundings. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1305.4932v2-abstract-full').style.display = 'none'; document.getElementById('1305.4932v2-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 May, 2013; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 21 May, 2013; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2013. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted to ApJ May 20, 2013, updated to correct a typo</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 771, Issue 2, article id. 132, 20 pp. (2013) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1211.1973">arXiv:1211.1973</a> <span> [<a href="https://arxiv.org/pdf/1211.1973">pdf</a>, <a href="https://arxiv.org/ps/1211.1973">ps</a>, <a href="https://arxiv.org/format/1211.1973">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/10.1088/0004-637X/761/2/145">10.1088/0004-637X/761/2/145 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Present-day Galactic Evolution: Low-metallicity, Warm, Ionized Gas Inflow Associated with High-Velocity Cloud Complex A </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Haffner%2C+L+M">Lawrence M. Haffner</a>, <a href="/search/?searchtype=author&query=Wakker%2C+B+P">Bart P. Wakker</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">Alex S. Hill</a>, <a href="/search/?searchtype=author&query=Madsen%2C+G+J">Greg J. Madsen</a>, <a href="/search/?searchtype=author&query=Duncan%2C+A+K">Allison K. Duncan</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="1211.1973v2-abstract-short" style="display: inline;"> The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the Galaxy. We present Wisconsin H-alpha Mapper (WHAM) kinematically resolved observations of Complex A over the velocity range of -250 to -50 km/s in the local standard… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1211.1973v2-abstract-full').style.display = 'inline'; document.getElementById('1211.1973v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1211.1973v2-abstract-full" style="display: none;"> The high-velocity cloud (HVC) Complex A is a probe of the physical conditions in the Galactic halo. The kinematics, morphology, distance, and metallicity of Complex A indicate that it represents new material that is accreting onto the Galaxy. We present Wisconsin H-alpha Mapper (WHAM) kinematically resolved observations of Complex A over the velocity range of -250 to -50 km/s in the local standard of rest reference frame. These observations include the first full H-alpha intensity map of Complex A across (l, b) = (124, 18) to (171, 53) and deep targeted observations in H-alpha, [S II]6716, [N II]6584, and [O I]6300 towards regions with high H I column densities, background quasars, and stars. The H-alpha data imply that the masses of neutral and ionized material in the cloud are similar, both being greater than a million solar masses. We find that the Bland-Hawthorn & Maloney (1999, 2001) model for the intensity of the ionizing radiation near the Milky Way is consistent with the known distance of the high-latitude part of Complex A and an assumed cloud geometry that puts the lower-latitude parts of the cloud at a distance of 7 to 8 kpc. This compatibility implies a 5% ionizing photon escape fraction from the Galactic disk. We also provide the nitrogen and sulfur upper abundance solutions for a series of temperatures, metallicities, and cloud configurations for purely photoionized gas; these solutions are consistent with the sub-solar abundances found by previous studies, especially for temperatures above 10,000 K or for gas with a high fraction of singly-ionized nitrogen and sulfur. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1211.1973v2-abstract-full').style.display = 'none'; document.getElementById('1211.1973v2-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 August, 2013; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 8 November, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 2012. </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 Astrophysical Journal. Version 2 just updates the file format from manuscript to emulateapj. Some columns in Tables 4 & 5 have been removed so that they will fit</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> K. A. Barger et al. 2012, ApJ, 761, 145 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1209.1657">arXiv:1209.1657</a> <span> [<a href="https://arxiv.org/pdf/1209.1657">pdf</a>, <a href="https://arxiv.org/ps/1209.1657">ps</a>, <a href="https://arxiv.org/format/1209.1657">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="High Energy Astrophysical Phenomena">astro-ph.HE</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Instrumentation and Methods for Astrophysics">astro-ph.IM</span> <span class="tag is-small is-grey tooltip is-tooltip-top" data-tooltip="Space Physics">physics.space-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/10.1088/0004-637X/758/2/143">10.1088/0004-637X/758/2/143 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Observed Limits on Charge Exchange Contributions to the Diffuse X-ray Background </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Crowder%2C+S+G">S. G. Crowder</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=Brandl%2C+D+E">D. E. Brandl</a>, <a href="/search/?searchtype=author&query=Eckart%2C+M+E">M. E. Eckart</a>, <a href="/search/?searchtype=author&query=Galeazzi%2C+M">M. Galeazzi</a>, <a href="/search/?searchtype=author&query=Kelley%2C+R+L">R. L. Kelley</a>, <a href="/search/?searchtype=author&query=Kilbourne%2C+C+A">C. A. Kilbourne</a>, <a href="/search/?searchtype=author&query=McCammon%2C+D">D. McCammon</a>, <a href="/search/?searchtype=author&query=Pfendner%2C+C+G">C. G. Pfendner</a>, <a href="/search/?searchtype=author&query=Porter%2C+F+S">F. S. Porter</a>, <a href="/search/?searchtype=author&query=Rocks%2C+L">L. Rocks</a>, <a href="/search/?searchtype=author&query=Szymkowiak%2C+A+E">A. E. Szymkowiak</a>, <a href="/search/?searchtype=author&query=Teplin%2C+I+M">I. M. Teplin</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="1209.1657v1-abstract-short" style="display: inline;"> We present a high resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for a ~1 region of the sky centered at l=90, b=+60 using a 36-pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum's observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1209.1657v1-abstract-full').style.display = 'inline'; document.getElementById('1209.1657v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1209.1657v1-abstract-full" style="display: none;"> We present a high resolution spectrum of the diffuse X-ray background from 0.1 to 1 keV for a ~1 region of the sky centered at l=90, b=+60 using a 36-pixel array of microcalorimeters flown on a sounding rocket. With an energy resolution of 11 eV FWHM below 1 keV, the spectrum's observed line ratios help separate charge exchange contributions originating within the heliosphere from thermal emission of hot gas in the interstellar medium. The X-ray sensitivity below 1 keV was reduced by about a factor of four from contamination that occurred early in the flight, limiting the significance of the results. The observed centroid of helium-like O VII is 568+2-3 eV at 90% confidence. Since the centroid expected for thermal emission is 568.4 eV while for charge exchange is 564.2 eV, thermal emission appears to dominate for this line complex, consistent with much of the high-latitude O VII emission originating in 2-3 x 10^6 K gas in the Galactic halo. On the other hand, the observed ratio of C VI Ly gamma to Ly alpha is 0.3+-0.2. The expected ratios are 0.04 for thermal emission and 0.24 for charge exchange, indicating that charge exchange must contribute strongly to this line and therefore potentially to the rest of the ROSAT R12 band usually associated with 10^6 K emission from the Local Hot Bubble. The limited statistics of this experiment and systematic uncertainties due to the contamination require only >32% thermal emission for O VII and >20% from charge exchange for C VI at the 90% confidence level. An experimental gold coating on the silicon substrate of the array greatly reduced extraneous signals induced on nearby pixels from cosmic rays passing through the substrate, reducing the triggered event rate by a factor of 15 from a previous flight of the instrument. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1209.1657v1-abstract-full').style.display = 'none'; document.getElementById('1209.1657v1-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 September, 2012; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2012. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">14 pages, 7 figures, to be published in ApJ</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> 2012 ApJ 758 143 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1008.0612">arXiv:1008.0612</a> <span> [<a href="https://arxiv.org/pdf/1008.0612">pdf</a>, <a href="https://arxiv.org/ps/1008.0612">ps</a>, <a href="https://arxiv.org/format/1008.0612">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> <p class="title is-5 mathjax"> Early Results from the Wisconsin H-Alpha Mapper Southern Sky Survey </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Haffner%2C+L+M">L. M. Haffner</a>, <a href="/search/?searchtype=author&query=Reynolds%2C+R+J">R. J. Reynolds</a>, <a href="/search/?searchtype=author&query=Madsen%2C+G+J">G. J. Madsen</a>, <a href="/search/?searchtype=author&query=Hill%2C+A+S">A. S. Hill</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">K. A. Barger</a>, <a href="/search/?searchtype=author&query=Jaehnig%2C+K+P">K. P. Jaehnig</a>, <a href="/search/?searchtype=author&query=Mierkiewicz%2C+E+J">E. J. Mierkiewicz</a>, <a href="/search/?searchtype=author&query=Percival%2C+J+W">J. W. Percival</a>, <a href="/search/?searchtype=author&query=Chopra%2C+N">N. Chopra</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="1008.0612v1-abstract-short" style="display: inline;"> After a successful eleven-year campaign at Kitt Peak, we moved the Wisconsin H-Alpha Mapper (WHAM) to Cerro Tololo in early 2009. Here we present some of the early data after a few months under southern skies. These maps begin to complete the first all-sky, kinematic survey of the diffuse H-alpha emission from the Milky Way. Much of this emission arises from the Warm Ionized Medium (WIM), a signif… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1008.0612v1-abstract-full').style.display = 'inline'; document.getElementById('1008.0612v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1008.0612v1-abstract-full" style="display: none;"> After a successful eleven-year campaign at Kitt Peak, we moved the Wisconsin H-Alpha Mapper (WHAM) to Cerro Tololo in early 2009. Here we present some of the early data after a few months under southern skies. These maps begin to complete the first all-sky, kinematic survey of the diffuse H-alpha emission from the Milky Way. Much of this emission arises from the Warm Ionized Medium (WIM), a significant component of the ISM that extends a few kiloparsecs above the Galactic disk. While this first look at the data focuses on the H-alpha survey, WHAM is also capable of observing many other optical emission lines, revealing fascinating trends in the temperature and ionization state of the WIM. Our ongoing studies of the physical conditions of diffuse ionized gas will continue from the southern hemisphere following the H-alpha survey. In addition, future observations will cover the full velocity range of the Magellanic Stream, Bridge, and Clouds to trace the ionized gas associated with these neighboring systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1008.0612v1-abstract-full').style.display = 'none'; document.getElementById('1008.0612v1-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 August, 2010; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2010. </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. To appear in "The Dynamic ISM: A celebration of the Canadian Galactic Plane Survey," ASP Conference Series</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/0704.3066">arXiv:0704.3066</a> <span> [<a href="https://arxiv.org/pdf/0704.3066">pdf</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Astrophysics">astro-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/10.1063/1.2723066">10.1063/1.2723066 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Complex impedance measurements of calorimeters and bolometers: correction for stray impedances </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Lindeman%2C+M+A">Mark. A. Lindeman</a>, <a href="/search/?searchtype=author&query=Barger%2C+K+A">Kathleen A. Barger</a>, <a href="/search/?searchtype=author&query=Brandl%2C+D+E">Donald E. Brandl</a>, <a href="/search/?searchtype=author&query=Crowder%2C+S+G">S. Gwynne Crowder</a>, <a href="/search/?searchtype=author&query=Rocks%2C+L">Lindsay Rocks</a>, <a href="/search/?searchtype=author&query=McCammon%2C+D">Dan McCammon</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="0704.3066v1-abstract-short" style="display: inline;"> Impedance measurements provide a useful probe of the physics of bolometers and calorimeters. We describe a method for measuring the complex impedance of these devices. In previous work, stray impedances and readout electronics of the measurement apparatus have resulted in artifacts in the impedance data. The new technique allows experimenters to find an independent Thevenin or Norton equivalent… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0704.3066v1-abstract-full').style.display = 'inline'; document.getElementById('0704.3066v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="0704.3066v1-abstract-full" style="display: none;"> Impedance measurements provide a useful probe of the physics of bolometers and calorimeters. We describe a method for measuring the complex impedance of these devices. In previous work, stray impedances and readout electronics of the measurement apparatus have resulted in artifacts in the impedance data. The new technique allows experimenters to find an independent Thevenin or Norton equivalent circuit for each frequency. This method allows experimenters to easily isolate the device impedance from the effects of parasitic impedances and frequency dependent gains in amplifiers. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('0704.3066v1-abstract-full').style.display = 'none'; document.getElementById('0704.3066v1-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 April, 2007; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> April 2007. </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, 6 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Rev.Sci.Instrum.78:043105,2007 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/hep-ph/9406331">arXiv:hep-ph/9406331</a> <span> [<a href="https://arxiv.org/pdf/hep-ph/9406331">pdf</a>, <a href="https://arxiv.org/ps/hep-ph/9406331">ps</a>, <a href="https://arxiv.org/format/hep-ph/9406331">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 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/10.1103/PhysRevD.51.90">10.1103/PhysRevD.51.90 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Hadron collider limits on anomalous $WW纬$ couplings </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/?searchtype=author&query=Barger%2C+K+R">Kevin R. Barger</a>, <a href="/search/?searchtype=author&query=Reno%2C+M+H">M. H. Reno</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="hep-ph/9406331v1-abstract-short" style="display: inline;"> A next-to-leading log calculation of the reactions $pp$ and $p\overline{p}\rightarrow W^\pm纬X$ is presented including a tri-boson gauge coupling from non-Standard Model contributions. Two approaches are made for comparison. The first approach considers the tri-boson $WW纬$ coupling as being uniquely fixed by tree level unitarity at high energies to its Standard Model form and, consequently, suppr… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('hep-ph/9406331v1-abstract-full').style.display = 'inline'; document.getElementById('hep-ph/9406331v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="hep-ph/9406331v1-abstract-full" style="display: none;"> A next-to-leading log calculation of the reactions $pp$ and $p\overline{p}\rightarrow W^\pm纬X$ is presented including a tri-boson gauge coupling from non-Standard Model contributions. Two approaches are made for comparison. The first approach considers the tri-boson $WW纬$ coupling as being uniquely fixed by tree level unitarity at high energies to its Standard Model form and, consequently, suppresses the non-Standard Model contributions with form factors. The second approach is to ignore such considerations and calculate the contributions to non-Standard Model tri-boson gauge couplings without such suppressions. It is found that at Tevatron energies, the two approaches do not differ much in quantitative results, while at Large Hadron Collider (LHC) energies the two approaches give significantly different predictions for production rates. At the Tevatron and LHC, however, the sensitivity limits on the anomalous coupling of $WW纬$ are too weak to usefully constrain parameters in effective Lagrangian models. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('hep-ph/9406331v1-abstract-full').style.display = 'none'; document.getElementById('hep-ph/9406331v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 16 June, 1994; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 1994. </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">Revtex 23 pages + 8 figures, UIOWA-94-10</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Phys.Rev. D51 (1995) 90-98 </p> </li> </ol> <div class="is-hidden-tablet">  <span class="help" style="display: inline-block;"><a href="https://github.com/arXiv/arxiv-search/releases">Search v0.5.6 released 2020-02-24</a>  </span> </div> </div> </main> <footer> <div class="columns is-desktop" role="navigation" aria-label="Secondary">  <div class="column"> <div class="columns"> <div class="column"> <ul class="nav-spaced"> <li><a href="https://info.arxiv.org/about">About</a></li> <li><a href="https://info.arxiv.org/help">Help</a></li> </ul> </div> <div class="column"> <ul class="nav-spaced"> <li> <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" class="icon filter-black" role="presentation"><title>contact arXiv</title><desc>Click here to contact arXiv</desc><path d="M502.3 190.8c3.9-3.1 9.7-.2 9.7 4.7V400c0 26.5-21.5 48-48 48H48c-26.5 0-48-21.5-48-48V195.6c0-5 5.7-7.8 9.7-4.7 22.4 17.4 52.1 39.5 154.1 113.6 21.1 15.4 56.7 47.8 92.2 47.6 35.7.3 72-32.8 92.3-47.6 102-74.1 131.6-96.3 154-113.7zM256 320c23.2.4 56.6-29.2 73.4-41.4 132.7-96.3 142.8-104.7 173.4-128.7 5.8-4.5 9.2-11.5 9.2-18.9v-19c0-26.5-21.5-48-48-48H48C21.5 64 0 85.5 0 112v19c0 7.4 3.4 14.3 9.2 18.9 30.6 23.9 40.7 32.4 173.4 128.7 16.8 12.2 50.2 41.8 73.4 41.4z"/></svg> <a href="https://info.arxiv.org/help/contact.html"> Contact</a> </li> <li> <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" class="icon filter-black" role="presentation"><title>subscribe to arXiv mailings</title><desc>Click here to subscribe</desc><path d="M476 3.2L12.5 270.6c-18.1 10.4-15.8 35.6 2.2 43.2L121 358.4l287.3-253.2c5.5-4.9 13.3 2.6 8.6 8.3L176 407v80.5c0 23.6 28.5 32.9 42.5 15.8L282 426l124.6 52.2c14.2 6 30.4-2.9 33-18.2l72-432C515 7.8 493.3-6.8 476 3.2z"/></svg> <a href="https://info.arxiv.org/help/subscribe"> Subscribe</a> </li> </ul> </div> </div> </div>   <div class="column"> <div class="columns"> <div class="column"> <ul class="nav-spaced"> <li><a href="https://info.arxiv.org/help/license/index.html">Copyright</a></li> <li><a href="https://info.arxiv.org/help/policies/privacy_policy.html">Privacy Policy</a></li> </ul> </div> <div class="column sorry-app-links"> <ul class="nav-spaced"> <li><a href="https://info.arxiv.org/help/web_accessibility.html">Web Accessibility Assistance</a></li> <li> <p class="help"> <a class="a11y-main-link" href="https://status.arxiv.org" target="_blank">arXiv Operational Status <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 256 512" class="icon filter-dark_grey" role="presentation"><path d="M224.3 273l-136 136c-9.4 9.4-24.6 9.4-33.9 0l-22.6-22.6c-9.4-9.4-9.4-24.6 0-33.9l96.4-96.4-96.4-96.4c-9.4-9.4-9.4-24.6 0-33.9L54.3 103c9.4-9.4 24.6-9.4 33.9 0l136 136c9.5 9.4 9.5 24.6.1 34z"/></svg></a><br> Get status notifications via <a class="is-link" href="https://subscribe.sorryapp.com/24846f03/email/new" target="_blank"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512" class="icon filter-black" role="presentation"><path d="M502.3 190.8c3.9-3.1 9.7-.2 9.7 4.7V400c0 26.5-21.5 48-48 48H48c-26.5 0-48-21.5-48-48V195.6c0-5 5.7-7.8 9.7-4.7 22.4 17.4 52.1 39.5 154.1 113.6 21.1 15.4 56.7 47.8 92.2 47.6 35.7.3 72-32.8 92.3-47.6 102-74.1 131.6-96.3 154-113.7zM256 320c23.2.4 56.6-29.2 73.4-41.4 132.7-96.3 142.8-104.7 173.4-128.7 5.8-4.5 9.2-11.5 9.2-18.9v-19c0-26.5-21.5-48-48-48H48C21.5 64 0 85.5 0 112v19c0 7.4 3.4 14.3 9.2 18.9 30.6 23.9 40.7 32.4 173.4 128.7 16.8 12.2 50.2 41.8 73.4 41.4z"/></svg>email</a> or <a class="is-link" href="https://subscribe.sorryapp.com/24846f03/slack/new" target="_blank"><svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 448 512" class="icon filter-black" role="presentation"><path d="M94.12 315.1c0 25.9-21.16 47.06-47.06 47.06S0 341 0 315.1c0-25.9 21.16-47.06 47.06-47.06h47.06v47.06zm23.72 0c0-25.9 21.16-47.06 47.06-47.06s47.06 21.16 47.06 47.06v117.84c0 25.9-21.16 47.06-47.06 47.06s-47.06-21.16-47.06-47.06V315.1zm47.06-188.98c-25.9 0-47.06-21.16-47.06-47.06S139 32 164.9 32s47.06 21.16 47.06 47.06v47.06H164.9zm0 23.72c25.9 0 47.06 21.16 47.06 47.06s-21.16 47.06-47.06 47.06H47.06C21.16 243.96 0 222.8 0 196.9s21.16-47.06 47.06-47.06H164.9zm188.98 47.06c0-25.9 21.16-47.06 47.06-47.06 25.9 0 47.06 21.16 47.06 47.06s-21.16 47.06-47.06 47.06h-47.06V196.9zm-23.72 0c0 25.9-21.16 47.06-47.06 47.06-25.9 0-47.06-21.16-47.06-47.06V79.06c0-25.9 21.16-47.06 47.06-47.06 25.9 0 47.06 21.16 47.06 47.06V196.9zM283.1 385.88c25.9 0 47.06 21.16 47.06 47.06 0 25.9-21.16 47.06-47.06 47.06-25.9 0-47.06-21.16-47.06-47.06v-47.06h47.06zm0-23.72c-25.9 0-47.06-21.16-47.06-47.06 0-25.9 21.16-47.06 47.06-47.06h117.84c25.9 0 47.06 21.16 47.06 47.06 0 25.9-21.16 47.06-47.06 47.06H283.1z"/></svg>slack</a> </p> </li> </ul> </div> </div> </div>  </div> </footer> <script src="https://static.arxiv.org/static/base/1.0.0a5/js/member_acknowledgement.js"></script> </body> </html>

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