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<button class="button is-small is-link">Go</button> </div> </div> </form> </div> </div> <ol class="breathe-horizontal" start="1"> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2312.09756">arXiv:2312.09756</a> <span> [<a href="https://arxiv.org/pdf/2312.09756">pdf</a>, <a href="https://arxiv.org/format/2312.09756">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> <p class="title is-5 mathjax"> The VISCACHA survey -- IX. The SMC Southern Bridge in 8D </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Parisi%2C+M+C">M. C. Parisi</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">R. A. P. Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=Angelo%2C+M">M. Angelo</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">B. Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F">F. Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Saroon%2C+S">S. Saroon</a>, <a href="/search/astro-ph?searchtype=author&query=Feinstein%2C+C">C. Feinstein</a>, <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C">J. F. C. Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">E. Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Ferreira%2C+B+P+L">B. Pereira Lima Ferreira</a>, <a href="/search/astro-ph?searchtype=author&query=Fern%C3%A1ndez-Trincado%2C+J+G">J. G. Fern谩ndez-Trincado</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Minniti%2C+D">D. Minniti</a>, <a href="/search/astro-ph?searchtype=author&query=Garro%2C+E+R">E. R. Garro</a>, <a href="/search/astro-ph?searchtype=author&query=Santrich%2C+O+J+K">O. J. Katime Santrich</a>, <a href="/search/astro-ph?searchtype=author&query=De+Bortoli%2C+B">B. De Bortoli</a>, <a href="/search/astro-ph?searchtype=author&query=Souza%2C+S">S. Souza</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L">L. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=P%C3%A9rez-Villegas%2C+A">A. P茅rez-Villegas</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="2312.09756v1-abstract-short" style="display: inline;"> The structure of the Small Magellanic Cloud (SMC) outside of its main body is characterised by tidal branches resulting from its interactions mainly with the Large Magellanic Cloud (LMC). Characterising the stellar populations in these tidal components helps to understand the dynamical history of this galaxy and of the Magellanic system in general. We provide full phase-space vector information fo… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.09756v1-abstract-full').style.display = 'inline'; document.getElementById('2312.09756v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2312.09756v1-abstract-full" style="display: none;"> The structure of the Small Magellanic Cloud (SMC) outside of its main body is characterised by tidal branches resulting from its interactions mainly with the Large Magellanic Cloud (LMC). Characterising the stellar populations in these tidal components helps to understand the dynamical history of this galaxy and of the Magellanic system in general. We provide full phase-space vector information for Southern Bridge clusters. We performed a photometric and spectroscopic analysis of twelve SMC clusters, doubling the number of SMC clusters with full phase-space vector information known to date. We reclassify the sample considering 3D distances and 3D velocities. We found that some of the clusters classified as Southern Bridge objects according to the projected 2D classification actually belong to the Main Body and Counter-Bridge in the background. The comparison of the kinematics of the genuine foreground Bridge clusters with those previously analysed in the same way reveals that Southern Bridge clusters are moving towards the LMC and share the kinematics of the Northern Bridge. Adding to our sample clusters from the literature with CaT metallicity determinations we compare the age-metallicity relation of the Southern Bridge with the one of the Northern Bridge. We reinforce the idea that both regions do not seem to have experienced the same chemical enrichment history and that there is a clear absence of clusters in the Northern Bridge older than 3Gyr and more metal-poor than -1.1, which would not seem to be due to a selection effect. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2312.09756v1-abstract-full').style.display = 'none'; document.getElementById('2312.09756v1-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, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2023. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">18 pages, 9 figures, accepted for publication in MNRAS</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2310.15158">arXiv:2310.15158</a> <span> [<a href="https://arxiv.org/pdf/2310.15158">pdf</a>, <a href="https://arxiv.org/format/2310.15158">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/stad3276">10.1093/mnras/stad3276 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Ages and metallicities of stellar clusters using S-PLUS narrow-band integrated photometry: the Small Magellanic Cloud </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=de+Souza%2C+G+F">Gabriel Fabiano de Souza</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Almeida-Fernandes%2C+F">Felipe Almeida-Fernandes</a>, <a href="/search/astro-ph?searchtype=author&query=Limberg%2C+G">Guilherme Limberg</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">Bruno Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Hernandez-Jimenez%2C+J+A">Jos茅 A. Hernandez-Jimenez</a>, <a href="/search/astro-ph?searchtype=author&query=Herpich%2C+F+R">F谩bio R. Herpich</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L+O">Leandro O. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Machado-Pereira%2C+E">Eduardo Machado-Pereira</a>, <a href="/search/astro-ph?searchtype=author&query=Perottoni%2C+H+D">H茅lio D. Perottoni</a>, <a href="/search/astro-ph?searchtype=author&query=Guer%C3%A7o%2C+R">Rafael Guer莽o</a>, <a href="/search/astro-ph?searchtype=author&query=Li%2C+L">Liana Li</a>, <a href="/search/astro-ph?searchtype=author&query=Sampedro%2C+L">Laura Sampedro</a>, <a href="/search/astro-ph?searchtype=author&query=Kanaan%2C+A">Antonio Kanaan</a>, <a href="/search/astro-ph?searchtype=author&query=Ribeiro%2C+T">Tiago Ribeiro</a>, <a href="/search/astro-ph?searchtype=author&query=Schoenell%2C+W">William Schoenell</a>, <a href="/search/astro-ph?searchtype=author&query=de+Oliveira%2C+C+M">Claudia Mendes de Oliveira</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="2310.15158v2-abstract-short" style="display: inline;"> The Magellanic Clouds are the most massive and closest satellite galaxies of the Milky Way, with stars covering ages from a few Myr up to 13 Gyr. This makes them important for validating integrated light methods to study stellar populations and star-formation processes, which can be applied to more distant galaxies. We characterized a set of stellar clusters in the Small Magellanic Cloud (SMC), us… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2310.15158v2-abstract-full').style.display = 'inline'; document.getElementById('2310.15158v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2310.15158v2-abstract-full" style="display: none;"> The Magellanic Clouds are the most massive and closest satellite galaxies of the Milky Way, with stars covering ages from a few Myr up to 13 Gyr. This makes them important for validating integrated light methods to study stellar populations and star-formation processes, which can be applied to more distant galaxies. We characterized a set of stellar clusters in the Small Magellanic Cloud (SMC), using the $\textit{Southern Photometric Local Universe Survey}$. This is the first age (metallicity) determination for 11 (65) clusters of this sample. Through its 7 narrow bands, centered on important spectral features, and 5 broad bands, we can retrieve detailed information about stellar populations. We obtained ages and metallicities for all stellar clusters using the Bayesian spectral energy distribution fitting code $\texttt{BAGPIPES}$. With a sample of clusters in the color range $-0.20 < r-z < +0.35$, for which our determined parameters are most reliable, we modeled the age-metallicity relation of SMC. At any given age, the metallicities of SMC clusters are lower than those of both the Gaia Sausage-Enceladus disrupted dwarf galaxy and the Milky Way. In comparison with literature values, differences are $螖$log(age)$\approx0.31$ and $螖$[Fe/H]$\approx0.41$, which is comparable to low-resolution spectroscopy of individual stars. Finally, we confirm a previously known gradient, with younger clusters in the center and older ones preferentially located in the outermost regions. On the other hand, we found no evidence of a significant metallicity gradient. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2310.15158v2-abstract-full').style.display = 'none'; document.getElementById('2310.15158v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 30 November, 2023; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 23 October, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 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">12 pages, 11 figures</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Monthly Notices of the Royal Astronomical Society, Volume 527, Issue 2, January 2024, Pages 1733-1744 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2307.08709">arXiv:2307.08709</a> <span> [<a href="https://arxiv.org/pdf/2307.08709">pdf</a>, <a href="https://arxiv.org/format/2307.08709">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/10.1051/0004-6361/202346648">10.1051/0004-6361/202346648 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The VISCACHA survey -- VIII. Chemical evolution history of Small Magellanic Cloud West Halo cluster </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Saroon%2C+S">S. Saroon</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">B. Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Tsujimotto%2C+T">T. Tsujimotto</a>, <a href="/search/astro-ph?searchtype=author&query=Parisi%2C+M+C">M. C. Parisi</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F">F. Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L">L. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Bekki%2C+K">K. Bekki</a>, <a href="/search/astro-ph?searchtype=author&query=Minniti%2C+D">D. Minniti</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">R. A. P. Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Santrich%2C+O+J+K">O. J. K. Santrich</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">E. Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Sanmartim%2C+D">D. Sanmartim</a>, <a href="/search/astro-ph?searchtype=author&query=Quint%2C+B+C">B. C. Quint</a>, <a href="/search/astro-ph?searchtype=author&query=Fraga%2C+L">L. Fraga</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="2307.08709v1-abstract-short" style="display: inline;"> The chemical evolution history of the Small Magellanic Cloud (SMC) has been a matter of debate for decades. The challenges in understanding the SMC chemical evolution are related to a very slow star formation rate (SFR) combined with bursts triggered by the multiple interactions between the SMC and the Large Magellanic Cloud, a significant (~0.5 dex) metallicity dispersion for the SMC cluster popu… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.08709v1-abstract-full').style.display = 'inline'; document.getElementById('2307.08709v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2307.08709v1-abstract-full" style="display: none;"> The chemical evolution history of the Small Magellanic Cloud (SMC) has been a matter of debate for decades. The challenges in understanding the SMC chemical evolution are related to a very slow star formation rate (SFR) combined with bursts triggered by the multiple interactions between the SMC and the Large Magellanic Cloud, a significant (~0.5 dex) metallicity dispersion for the SMC cluster population younger than about 7.5 Gyr, and multiple chemical evolution models tracing very different paths through the observed age-metallicity relation of the SMC. There is no doubt that these processes were complex. Therefore, a step-by-step strategy is required in order to better understand the SMC chemical evolution. We adopted an existing framework to split the SMC into regions on the sky, and we focus on the west halo in this work, which contains the oldest and most metal-poor stellar populations and is moving away from the SMC, that is, in an opposite motion with respect to the Magellanic Bridge. We present a sample containing ~60% of all west halo clusters to represent the region well, and we identify a clear age-metallicity relation with a tight dispersion that exhibits a 0.5 dex metallicity dip about 6 Gyr ago. We ran chemical evolution models and discuss possible scenarios to explain this metallicity dip, the most likely being a major merger accelerating the SFR after the event. This merger should be combined with inefficient internal gas mixing within the SMC and different SFRs in different SMC regions because the same metallicity dip is not seen in the AMR of the SMC combining clusters from all regions. We try to explain the scenario to better understand the SMC chemo-dynamical history. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2307.08709v1-abstract-full').style.display = 'none'; document.getElementById('2307.08709v1-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 July, 2023; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">16 pages, 8 figures, 3 tables, Accepted for publication in Astronomy & Astrophysics journals</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 677, A35 (2023) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2103.02600">arXiv:2103.02600</a> <span> [<a href="https://arxiv.org/pdf/2103.02600">pdf</a>, <a href="https://arxiv.org/format/2103.02600">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/10.1051/0004-6361/202040015">10.1051/0004-6361/202040015 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The VISCACHA survey -- III. Star clusters counterpart of the Magellanic Bridge and Counter-Bridge in 8D </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">B. Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Angelo%2C+M+S">M. S. Angelo</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">R. A. P. Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F">F. Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Parisi%2C+M+C">M. C. Parisi</a>, <a href="/search/astro-ph?searchtype=author&query=De+Bortoli%2C+B">B. De Bortoli</a>, <a href="/search/astro-ph?searchtype=author&query=Souza%2C+S+O">S. O. Souza</a>, <a href="/search/astro-ph?searchtype=author&query=Santrich%2C+O+J+K">O. J. Katime Santrich</a>, <a href="/search/astro-ph?searchtype=author&query=Bassino%2C+L+P">L. P. Bassino</a>, <a href="/search/astro-ph?searchtype=author&query=Barbuy%2C+B">B. Barbuy</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">E. Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Geisler%2C+D">D. Geisler</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L">L. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=P%C3%A9rez-Villegas%2C+A">A. P茅rez-Villegas</a>, <a href="/search/astro-ph?searchtype=author&query=Quint%2C+B">B. Quint</a>, <a href="/search/astro-ph?searchtype=author&query=Sanmartim%2C+D">D. Sanmartim</a>, <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C">J. F. C. Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</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="2103.02600v1-abstract-short" style="display: inline;"> Context. The interactions between the SMC and LMC created the Magellanic Bridge, a stream of gas and stars pulled out of the SMC towards the LMC about 150 Myr ago. The tidal counterpart of this structure, which should include a trailing arm, has been predicted by models but no compelling observational evidence has confirmed the Counter-Bridge so far. Aims. The main goal of this work is to find the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.02600v1-abstract-full').style.display = 'inline'; document.getElementById('2103.02600v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2103.02600v1-abstract-full" style="display: none;"> Context. The interactions between the SMC and LMC created the Magellanic Bridge, a stream of gas and stars pulled out of the SMC towards the LMC about 150 Myr ago. The tidal counterpart of this structure, which should include a trailing arm, has been predicted by models but no compelling observational evidence has confirmed the Counter-Bridge so far. Aims. The main goal of this work is to find the stellar counterpart of the Magellanic Bridge and Counter-Bridge. We use star clusters in the SMC outskirts as they provide 6D phase-space vector, age and metallicity that help characterise the outskirts of the SMC. Methods. Distances, ages and photometric metallicities are derived from fitting isochrones to the colour-magnitude diagrams from the VISCACHA survey. Radial velocities and spectroscopic metallicities are derived from the spectroscopic follow-up using GMOS in the CaII triplet region. Results. Among the seven clusters analysed in this work, five belong to the Magellanic Bridge and one belongs to the Counter-Bridge and the other to the transition region. Conclusions. The existence of the tidal counterpart of the Magellanic Bridge is evidenced by star clusters. The stellar component of the Magellanic Bridge and Counter-Bridge are confirmed in the SMC outskirts. These results are an important constraint for models that seek to reconstruct the history of the orbit and interactions between LMC-SMC and constrain their future interaction including with the Milky Way. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2103.02600v1-abstract-full').style.display = 'none'; document.getElementById('2103.02600v1-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 March, 2021; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">10 pages, 7 figures. Astronomy and Astrophysics Letter, accepted. For associated video file (fig.A.4), see https://drive.google.com/file/d/1mSx3z6vDjHUneEeVq1i-MHwXZ1O0pZ-f</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> A&A 647, L9 (2021) </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/2008.04399">arXiv:2008.04399</a> <span> [<a href="https://arxiv.org/pdf/2008.04399">pdf</a>, <a href="https://arxiv.org/ps/2008.04399">ps</a>, <a href="https://arxiv.org/format/2008.04399">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/staa2425">10.1093/mnras/staa2425 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The VISCACHA survey -- II. Structure of star clusters in the Magellanic Clouds periphery </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C">J. F. C. Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F+F+S">F. F. S. Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">B. Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L+d+O">L. de O. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Piatti%2C+A+E">A. E. Piatti</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">E. Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Angelo%2C+M+S">M. S. Angelo</a>, <a href="/search/astro-ph?searchtype=author&query=Minniti%2C+D">D. Minniti</a>, <a href="/search/astro-ph?searchtype=author&query=P%C3%A9rez-Villegas%2C+A">A. P茅rez-Villegas</a>, <a href="/search/astro-ph?searchtype=author&query=Roman-Lopes%2C+A">A. Roman-Lopes</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Fraga%2C+L">L. Fraga</a>, <a href="/search/astro-ph?searchtype=author&query=Quint%2C+B">B. Quint</a>, <a href="/search/astro-ph?searchtype=author&query=Sanmartim%2C+D">D. Sanmartim</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="2008.04399v1-abstract-short" style="display: inline;"> We provide a homogeneous set of structural parameters of 83 star clusters located at the periphery of the Small Magellanic Cloud (SMC) and the Large Magellanic Cloud (LMC). The clusters' stellar density and surface brightness profiles were built from deep, AO assisted optical images, and uniform analysis techniques. The structural parameters were obtained from King and Elson et al. model fittings.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.04399v1-abstract-full').style.display = 'inline'; document.getElementById('2008.04399v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="2008.04399v1-abstract-full" style="display: none;"> We provide a homogeneous set of structural parameters of 83 star clusters located at the periphery of the Small Magellanic Cloud (SMC) and the Large Magellanic Cloud (LMC). The clusters' stellar density and surface brightness profiles were built from deep, AO assisted optical images, and uniform analysis techniques. The structural parameters were obtained from King and Elson et al. model fittings. Integrated magnitudes and masses (for a subsample) are also provided. The sample contains mostly low surface brightness clusters with distances between 4.5 and 6.5 kpc and between 1 and 6.5 kpc from the LMC and SMC centres, respectively. We analysed their spatial distribution and structural properties, comparing them with those of inner clusters. Half-light and Jacobi radii were estimated, allowing an evaluation of the Roche volume tidal filling. We found that: (i) for our sample of LMC clusters, the tidal radii are, on average, larger than those of inner clusters from previous studies; (ii) the core radii dispersion tends to be greater for LMC clusters located towards the southwest, with position angles of $\sim$200 degrees and about $\sim$5 degrees from the LMC centre, i.e., those LMC clusters nearer to the SMC; (iii) the core radius evolution for clusters with known age is similar to that of inner clusters; (iv) SMC clusters with galactocentric distances closer than 4 kpc are overfilling; (v) the recent Clouds collision did not leave marks on the LMC clusters' structure that our analysis could reveal. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('2008.04399v1-abstract-full').style.display = 'none'; document.getElementById('2008.04399v1-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 August, 2020; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2020. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">19 pages, 16 figures, accepted by MNRAS. Full tables and additional plots included</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1909.02566">arXiv:1909.02566</a> <span> [<a href="https://arxiv.org/pdf/1909.02566">pdf</a>, <a href="https://arxiv.org/format/1909.02566">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> <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/10.1017/S174392131900694X">10.1017/S174392131900694X <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The VISCACHA survey -- deep and resolved photometry of star clusters in the Magellanic Clouds </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">Bruno Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F">Francisco Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L">Leandro Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C+d">Jo茫o F. C. dos Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">Eduardo Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Armond%2C+T">Tina Armond</a>, <a href="/search/astro-ph?searchtype=author&query=Barbuy%2C+B">Beatriz Barbuy</a>, <a href="/search/astro-ph?searchtype=author&query=Fraga%2C+L">Luciano Fraga</a>, <a href="/search/astro-ph?searchtype=author&query=Hernandez-Jimenez%2C+J+A">Jose A. Hernandez-Jimenez</a>, <a href="/search/astro-ph?searchtype=author&query=Santrich%2C+O+J+K">Orlando J. Katime Santrich</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">Raphael A. P. Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=P%C3%A9rez-Villegas%2C+A">Angeles P茅rez-Villegas</a>, <a href="/search/astro-ph?searchtype=author&query=Piatti%2C+A">Andres Piatti</a>, <a href="/search/astro-ph?searchtype=author&query=Quint%2C+B">Bruno Quint</a>, <a href="/search/astro-ph?searchtype=author&query=Sanmartin%2C+D">David Sanmartin</a>, <a href="/search/astro-ph?searchtype=author&query=Angelo%2C+M+S">Mateus S. Angelo</a>, <a href="/search/astro-ph?searchtype=author&query=Souza%2C+S+O">Stefano O. Souza</a>, <a href="/search/astro-ph?searchtype=author&query=Vieira%2C+R+G">Rodrigo G. Vieira</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Parisi%2C+C">Celeste Parisi</a>, <a href="/search/astro-ph?searchtype=author&query=Geisler%2C+D">Doug Geisler</a>, <a href="/search/astro-ph?searchtype=author&query=Minniti%2C+D">Dante Minniti</a>, <a href="/search/astro-ph?searchtype=author&query=Saito%2C+R">Roberto Saito</a>, <a href="/search/astro-ph?searchtype=author&query=Bassino%2C+L">Lilia Bassino</a>, <a href="/search/astro-ph?searchtype=author&query=De+Bortoli%2C+B">Bruno De Bortoli</a> , et al. (2 additional authors not shown) </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1909.02566v1-abstract-short" style="display: inline;"> The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA\footnote{LMC and SMC names in the Tupi-Guarani language spoken by native people in Brazil}) Survey is an ongoing project based on deep and spatiallyresolved photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Mod… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1909.02566v1-abstract-full').style.display = 'inline'; document.getElementById('1909.02566v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1909.02566v1-abstract-full" style="display: none;"> The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA\footnote{LMC and SMC names in the Tupi-Guarani language spoken by native people in Brazil}) Survey is an ongoing project based on deep and spatiallyresolved photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Module Imager. So far we have used $>$300h of telescope time to observe $\sim$150 star clusters, mostly with low mass ($M < 10^4 M_{\odot}$) on the outskirts of the LMC and SMC. With this high-quality data set, we homogeneously determine physical properties using deep colour-magnitude diagrams (ages, metallicities, reddening, distances, mass, luminosity and mass functions) and structural parameters (radial density profiles, sizes) for these clusters which are used as a proxy to investigate the interplay between the Magellanic Clouds and their evolution. We present the VISCACHA survey and its initial results, based on our first two papers. The project's long term goals and expected legacy to the community are also addressed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1909.02566v1-abstract-full').style.display = 'none'; document.getElementById('1909.02566v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 September, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> September 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">4 pages, 2 figures, to appear in the proceedings of the IAUS351 "Star Clusters: From the Milky Way to the Early Universe", A. Bragaglia, M.B. Davies, A. Sills & E. Vesperini, eds</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> IAU-19-IAUS351-0212 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1907.08642">arXiv:1907.08642</a> <span> [<a href="https://arxiv.org/pdf/1907.08642">pdf</a>, <a href="https://arxiv.org/format/1907.08642">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/ab6595">10.3847/1538-3881/ab6595 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> An Updated SMC and Magellanic Bridge Catalog of Star Clusters, Associations and Related Objects </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">Eduardo Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L+d+O">Leandro de O. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">Bruno Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F">Francisco Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C">Jo茫o F. C. Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Barbuy%2C+B">Beatriz Barbuy</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">Raphael A. P. Oliveira</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="1907.08642v2-abstract-short" style="display: inline;"> We present a catalog of star clusters, associations and related extended objects in the Small Magellanic Cloud and the Magellanic Bridge with 2741 entries, a factor 2 more than a previous version from a decade ago. Literature data till December 2018 are included. The identification of star clusters was carried out with digital atlases in various bands currently available in DSS and MAMA imaging su… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.08642v2-abstract-full').style.display = 'inline'; document.getElementById('1907.08642v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1907.08642v2-abstract-full" style="display: none;"> We present a catalog of star clusters, associations and related extended objects in the Small Magellanic Cloud and the Magellanic Bridge with 2741 entries, a factor 2 more than a previous version from a decade ago. Literature data till December 2018 are included. The identification of star clusters was carried out with digital atlases in various bands currently available in DSS and MAMA imaging surveys. In particular, we cross-identified recent cluster samples from the VMC, OGLE-IV and SMASH surveys, confirming new clusters and pointing out equivalencies. A major contribution of the present catalog consists in the accurate central positions for clusters and small associations, including a new sample of 45 clusters or candidates in the SMC and 19 in the Bridge, as well as a compilation of the most reliable age and metallicity values from the literature. A general catalog must also deal with the recent discoveries of 27 faint and ultra-faint star clusters and galaxies projected on the far surroundings of the Clouds, most of them from the DES survey. The information on these objects has been complemented with photometric, spectroscopic and kinematical follow-up data from the literature. The underluminous galaxies around the Magellanic System, still very few as compared to the predictions from $螞$ Cold Dark Matter simulations, can bring constraints to galaxy formation and hierarchical evolution. Furthermore, we provide diagnostics, when possible, of the nature of the ultra-faint clusters, searching for borders of the Magellanic System extensions into the Milky Way gravitational potential. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.08642v2-abstract-full').style.display = 'none'; document.getElementById('1907.08642v2-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 9 January, 2020; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 19 July, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 13 figures and 4 tables. Updated to match accepted version in AJ. The updated catalog is provided in full as ancillary file</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1907.01567">arXiv:1907.01567</a> <span> [<a href="https://arxiv.org/pdf/1907.01567">pdf</a>, <a href="https://arxiv.org/format/1907.01567">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> <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="Solar and Stellar Astrophysics">astro-ph.SR</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/stz1985">10.1093/mnras/stz1985 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The Southern Photometric Local Universe Survey (S-PLUS): improved SEDs, morphologies and redshifts with 12 optical filters </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=de+Oliveira%2C+C+M">C. Mendes de Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=Ribeiro%2C+T">T. Ribeiro</a>, <a href="/search/astro-ph?searchtype=author&query=Schoenell%2C+W">W. Schoenell</a>, <a href="/search/astro-ph?searchtype=author&query=Kanaan%2C+A">A. Kanaan</a>, <a href="/search/astro-ph?searchtype=author&query=Overzier%2C+R+A">R. A. Overzier</a>, <a href="/search/astro-ph?searchtype=author&query=Molino%2C+A">A. Molino</a>, <a href="/search/astro-ph?searchtype=author&query=Sampedro%2C+L">L. Sampedro</a>, <a href="/search/astro-ph?searchtype=author&query=Coelho%2C+P">P. Coelho</a>, <a href="/search/astro-ph?searchtype=author&query=Barbosa%2C+C+E">C. E. Barbosa</a>, <a href="/search/astro-ph?searchtype=author&query=Cortesi%2C+A">A. Cortesi</a>, <a href="/search/astro-ph?searchtype=author&query=Costa-Duarte%2C+M+V">M. V. Costa-Duarte</a>, <a href="/search/astro-ph?searchtype=author&query=Herpich%2C+F+R">F. R. Herpich</a>, <a href="/search/astro-ph?searchtype=author&query=Hernandez-Jimenez%2C+J+A">J. A. Hernandez-Jimenez</a>, <a href="/search/astro-ph?searchtype=author&query=Placco%2C+V+M">V. M. Placco</a>, <a href="/search/astro-ph?searchtype=author&query=Xavier%2C+H+S">H. S. Xavier</a>, <a href="/search/astro-ph?searchtype=author&query=Abramo%2C+L+R">L. R. Abramo</a>, <a href="/search/astro-ph?searchtype=author&query=Saito%2C+R+K">R. K. Saito</a>, <a href="/search/astro-ph?searchtype=author&query=Chies-Santos%2C+A+L">A. L. Chies-Santos</a>, <a href="/search/astro-ph?searchtype=author&query=Ederoclite%2C+A">A. Ederoclite</a>, <a href="/search/astro-ph?searchtype=author&query=de+Oliveira%2C+R+L">R. Lopes de Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=Gon%C3%A7alves%2C+D+R">D. R. Gon莽alves</a>, <a href="/search/astro-ph?searchtype=author&query=Akras%2C+S">S. Akras</a>, <a href="/search/astro-ph?searchtype=author&query=Almeida%2C+L+A">L. A. Almeida</a>, <a href="/search/astro-ph?searchtype=author&query=Almeida-Fernandes%2C+F">F. Almeida-Fernandes</a>, <a href="/search/astro-ph?searchtype=author&query=Beers%2C+T+C">T. C. Beers</a> , et al. (120 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="1907.01567v2-abstract-short" style="display: inline;"> The Southern Photometric Local Universe Survey (S-PLUS) is imaging ~9300 deg^2 of the celestial sphere in twelve optical bands using a dedicated 0.8 m robotic telescope, the T80-South, at the Cerro Tololo Inter-American Observatory, Chile. The telescope is equipped with a 9.2k by 9.2k e2v detector with 10 um pixels, resulting in a field-of-view of 2 deg^2 with a plate scale of 0.55"/pixel. The sur… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.01567v2-abstract-full').style.display = 'inline'; document.getElementById('1907.01567v2-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1907.01567v2-abstract-full" style="display: none;"> The Southern Photometric Local Universe Survey (S-PLUS) is imaging ~9300 deg^2 of the celestial sphere in twelve optical bands using a dedicated 0.8 m robotic telescope, the T80-South, at the Cerro Tololo Inter-American Observatory, Chile. The telescope is equipped with a 9.2k by 9.2k e2v detector with 10 um pixels, resulting in a field-of-view of 2 deg^2 with a plate scale of 0.55"/pixel. The survey consists of four main subfields, which include two non-contiguous fields at high Galactic latitudes (8000 deg^2 at |b| > 30 deg) and two areas of the Galactic plane and bulge (for an additional 1300 deg^2). S-PLUS uses the Javalambre 12-band magnitude system, which includes the 5 u, g, r, i, z broad-band filters and 7 narrow-band filters centered on prominent stellar spectral features: the Balmer jump/[OII], Ca H+K, H-delta, G-band, Mg b triplet, H-alpha, and the Ca triplet. S-PLUS delivers accurate photometric redshifts (delta_z/(1+z) = 0.02 or better) for galaxies with r < 20 AB mag and redshift < 0.5, thus producing a 3D map of the local Universe over a volume of more than 1 (Gpc/h)^3. The final S-PLUS catalogue will also enable the study of star formation and stellar populations in and around the Milky Way and nearby galaxies, as well as searches for quasars, variable sources, and low-metallicity stars. In this paper we introduce the main characteristics of the survey, illustrated with science verification data highlighting the unique capabilities of S-PLUS. We also present the first public data release of ~336 deg^2 of the Stripe-82 area, which is available at http://datalab.noao.edu/splus. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1907.01567v2-abstract-full').style.display = 'none'; document.getElementById('1907.01567v2-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 September, 2019; <span class="has-text-black-bis has-text-weight-semibold">v1</span> submitted 2 July, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> July 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">Updated to reflect the published version (MNRAS, 489, 241). For a short introductory video of the S-PLUS project, see https://youtu.be/yc5kHrHU9Jk - The S-PLUS Data Release 1 is available at http://datalab.noao.edu/splus</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1902.01959">arXiv:1902.01959</a> <span> [<a href="https://arxiv.org/pdf/1902.01959">pdf</a>, <a href="https://arxiv.org/ps/1902.01959">ps</a>, <a href="https://arxiv.org/format/1902.01959">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Astrophysics of Galaxies">astro-ph.GA</span> </div> <div class="is-inline-block" style="margin-left: 0.5rem"> <div class="tags has-addons"> <span class="tag is-dark is-size-7">doi</span> <span class="tag is-light is-size-7"><a class="" href="https://doi.org/10.1093/mnras/stz369">10.1093/mnras/stz369 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> The VISCACHA survey - I. Overview and First Results </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Maia%2C+F+F+S">Francisco F. S. Maia</a>, <a href="/search/astro-ph?searchtype=author&query=Dias%2C+B">Bruno Dias</a>, <a href="/search/astro-ph?searchtype=author&query=Santos%2C+J+F+C">Jo茫o F. C. Santos Jr.</a>, <a href="/search/astro-ph?searchtype=author&query=Kerber%2C+L+d+O">Leandro de O. Kerber</a>, <a href="/search/astro-ph?searchtype=author&query=Bica%2C+E">Eduardo Bica</a>, <a href="/search/astro-ph?searchtype=author&query=Piatti%2C+A+E">Andr茅s E. Piatti</a>, <a href="/search/astro-ph?searchtype=author&query=Barbuy%2C+B">Beatriz Barbuy</a>, <a href="/search/astro-ph?searchtype=author&query=Quint%2C+B">Bruno Quint</a>, <a href="/search/astro-ph?searchtype=author&query=Fraga%2C+L">Luciano Fraga</a>, <a href="/search/astro-ph?searchtype=author&query=Sanmartim%2C+D">David Sanmartim</a>, <a href="/search/astro-ph?searchtype=author&query=Angelo%2C+M+S">Mateus S. Angelo</a>, <a href="/search/astro-ph?searchtype=author&query=Hernandez-Jimenez%2C+J+A">Jose A. Hernandez-Jimenez</a>, <a href="/search/astro-ph?searchtype=author&query=Santrich%2C+O+J+K">Orlando J. Katime Santrich</a>, <a href="/search/astro-ph?searchtype=author&query=Oliveira%2C+R+A+P">Raphael A. P. Oliveira</a>, <a href="/search/astro-ph?searchtype=author&query=P%C3%A9rez-Villegas%2C+A">Angeles P茅rez-Villegas</a>, <a href="/search/astro-ph?searchtype=author&query=Souza%2C+S+O">Stefano O. Souza</a>, <a href="/search/astro-ph?searchtype=author&query=Vieira%2C+R+G">Rodrigo G. Vieira</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a> </p> <p class="abstract mathjax"> <span class="has-text-black-bis has-text-weight-semibold">Abstract</span>: <span class="abstract-short has-text-grey-dark mathjax" id="1902.01959v1-abstract-short" style="display: inline;"> The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA) Survey is an ongoing project based on deep photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Module Imager. Since 2015 more than 200 hours of telescope time were used to observe about 130 stellar clusters, mos… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01959v1-abstract-full').style.display = 'inline'; document.getElementById('1902.01959v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1902.01959v1-abstract-full" style="display: none;"> The VISCACHA (VIsible Soar photometry of star Clusters in tApii and Coxi HuguA) Survey is an ongoing project based on deep photometric observations of Magellanic Cloud star clusters, collected using the SOuthern Astrophysical Research (SOAR) telescope together with the SOAR Adaptive Module Imager. Since 2015 more than 200 hours of telescope time were used to observe about 130 stellar clusters, most of them with low mass (M < 10$^4$ M$_\odot$) and/or located in the outermost regions of the Large Magellanic Cloud and the Small Magellanic Cloud. With this high quality data set, we homogeneously determine physical properties from statistical analysis of colour-magnitude diagrams, radial density profiles, luminosity functions and mass functions. Ages, metallicities, reddening, distances, present-day masses, mass function slopes and structural parameters for these clusters are derived and used as a proxy to investigate the interplay between the environment in the Magellanic Clouds and the evolution of such systems. In this first paper we present the VISCACHA Survey and its initial results, concerning the SMC clusters AM3, K37, HW20 and NGC796 and the LMC ones KMHK228, OHSC3, SL576, SL61 and SL897, chosen to compose a representative subset of our cluster sample. The project's long term goals and legacy to the community are also addressed. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1902.01959v1-abstract-full').style.display = 'none'; document.getElementById('1902.01959v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 5 February, 2019; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> February 2019. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">21 pages, 21 figures</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/1112.1227">arXiv:1112.1227</a> <span> [<a href="https://arxiv.org/pdf/1112.1227">pdf</a>, <a href="https://arxiv.org/ps/1112.1227">ps</a>, <a href="https://arxiv.org/format/1112.1227">other</a>] </span> </p> <div class="tags is-inline-block"> <span class="tag is-small is-link tooltip is-tooltip-top" data-tooltip="Cosmology and Nongalactic Astrophysics">astro-ph.CO</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/10.1111/j.1365-2966.2012.20314.x">10.1111/j.1365-2966.2012.20314.x <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gas and stellar metallicities in HII galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Cuisinier%2C+F">Fran莽ois Cuisinier</a>, <a href="/search/astro-ph?searchtype=author&query=Curty%2C+D">Didier Curty</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">Roland Buser</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="1112.1227v1-abstract-short" style="display: inline;"> We examine the gas and stellar metallicities in a sample of HII galaxies from the Sloan Digital Sky Survey, which possibly contains the largest homogeneous sample of HII galaxy spectra to date. We eliminated all spectra with an insufficient signal-to-noise ratio, without strong emission lines, and without the [OII] lambda3727 脜 line, which is necessary for the determination of the gas metallicity.… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1112.1227v1-abstract-full').style.display = 'inline'; document.getElementById('1112.1227v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="1112.1227v1-abstract-full" style="display: none;"> We examine the gas and stellar metallicities in a sample of HII galaxies from the Sloan Digital Sky Survey, which possibly contains the largest homogeneous sample of HII galaxy spectra to date. We eliminated all spectra with an insufficient signal-to-noise ratio, without strong emission lines, and without the [OII] lambda3727 脜 line, which is necessary for the determination of the gas metallicity. This excludes galaxies with redshift <~ 0.033. Our final sample contains ~700 spectra of HII galaxies. Through emission line strength calibrations and a detailed stellar population analysis employing evolutionary stellar synthesis methods, which we already used in previous works, we determined the metallicities of both the gas and the stellar content of these galaxies. We find that in HII galaxies up to stellar masses of 5\cdot10^9 M_sol, enrichment mechanisms do not vary with galactic mass, being the same for low- and high-mass galaxies on average. They do seem to present a greater variety at the high-mass end, though, indicating a more complex assembly history for high-mass galaxies. In around 23 per cent of our HII galaxies we find a metallicity decrease over the last few Gyr. Our results favour galaxy evolution models featuring constantly infalling low-metallicity clouds that retain part of the galactic winds. Above 5\cdot10^9 M_sol stellar mass, the retention of high metallicity gas by the galaxies' gravitational potential dominates. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('1112.1227v1-abstract-full').style.display = 'none'; document.getElementById('1112.1227v1-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 December, 2011; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2011. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">12 pages, 8 figures; accepted for publication in MNRAS</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">MSC Class:</span> 85 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0703728">arXiv:astro-ph/0703728</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0703728">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0703728">ps</a>, <a href="https://arxiv.org/format/astro-ph/0703728">other</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/10.1051/0004-6361:20065075">10.1051/0004-6361:20065075 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Initial mass function effects on the colour evolution of disk galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Samland%2C+M">M. Samland</a>, <a href="/search/astro-ph?searchtype=author&query=Kautsch%2C+S+J">S. J. Kautsch</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</a>, <a href="/search/astro-ph?searchtype=author&query=Ammon%2C+K">K. Ammon</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="astro-ph/0703728v1-abstract-short" style="display: inline;"> In this work, we want to find out if the IMF can be determined from colour images, integrated colours, or mass-to-light ratios, especially at high redshift, where galaxies cannot be resolved into individual stars, which would enable us to investigate dependencies of the IMF on cosmological epoch. We use chemo-dynamical models to investigate the influence of the Initial Mass Function (IMF) on the… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0703728v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0703728v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0703728v1-abstract-full" style="display: none;"> In this work, we want to find out if the IMF can be determined from colour images, integrated colours, or mass-to-light ratios, especially at high redshift, where galaxies cannot be resolved into individual stars, which would enable us to investigate dependencies of the IMF on cosmological epoch. We use chemo-dynamical models to investigate the influence of the Initial Mass Function (IMF) on the evolution of a Milky Way-type disk galaxy, in particular of its colours. We find that the effect of the IMF on the internal gas absorption is larger than its effect on the light from the stellar content. However, the two effects work in the opposite sense: An IMF with more high mass stars leads to brighter and bluer star-light, but also to more interstellar dust and thus to more absorption, causing a kind of "IMF degeneracy". The most likely wavelength region in which to detect IMF effects is the infrared (i. e., JHK). We also provide photometric absorption and inclination corrections in the SDSS ugriz and the HST WFPC2 and NICMOS systems. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0703728v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0703728v1-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 March, 2007; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 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">published in A&A, some figures have reduced resolution. For a full resolution version, see the A&A version</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astron.Astrophys.465:417-429,2007 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0608294">arXiv:astro-ph/0608294</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0608294">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0608294">ps</a>, <a href="https://arxiv.org/format/astro-ph/0608294">other</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/10.1086/508414">10.1086/508414 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Virgo cluster early-type dwarf galaxies with the Sloan Digital Sky Survey. II. Early-type dwarfs with central star formation </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lisker%2C+T">Thorsten Lisker</a>, <a href="/search/astro-ph?searchtype=author&query=Glatt%2C+K">Katharina Glatt</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Grebel%2C+E+K">Eva K. Grebel</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="astro-ph/0608294v1-abstract-short" style="display: inline;"> Despite the common picture of an early-type dwarf (dE) as a quiescent galaxy with no star formation and little gas, we identify 23 dEs that have blue central colors caused by recent or ongoing star formation in our sample of 476 Virgo cluster dEs. In addition, 14 objects that were mostly classified as (candidate) BCDs have similar properties. Among the certain cluster members, the dEs with blue… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0608294v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0608294v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0608294v1-abstract-full" style="display: none;"> Despite the common picture of an early-type dwarf (dE) as a quiescent galaxy with no star formation and little gas, we identify 23 dEs that have blue central colors caused by recent or ongoing star formation in our sample of 476 Virgo cluster dEs. In addition, 14 objects that were mostly classified as (candidate) BCDs have similar properties. Among the certain cluster members, the dEs with blue centers reach a fraction of more than 15% of the dE population at brighter (B<=16) magnitudes. A spectral analysis of the centers of 16 galaxies reveals in all cases an underlying old population that dominates the mass, with M(old)>=90% for all but one object. Therefore the majority of these galaxies will appear like ordinary dEs within ~one Gigayear or less after the last episode of star formation. Their overall gas content is less than that of dwarf irregular galaxies, but higher than that of ordinary dEs. Their flattening distribution suggests the shape of a thick disk, similar to what has been found for dEs with disk features in Paper I of this series. Their projected spatial distribution shows no central clustering, and their distribution with projected local density follows that of irregular galaxies, indicative of an unrelaxed population. This is corroborated by their velocity distribution, which displays two side peaks characteristic of recent infall. We discuss possible formation mechanisms (ram-pressure stripping, tidally induced star formation, harassment) that might be able to explain both the disk shape and the central star formation of the dEs with blue centers. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0608294v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0608294v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 14 August, 2006; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> August 2006. </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 + 15 figures. Accepted for publication in AJ. We recommend downloading the full resolution version from http://www.virgo-cluster.com/lisker2006b.ps.gz</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astron.J.132:2432-2452,2006 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0605206">arXiv:astro-ph/0605206</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0605206">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0605206">ps</a>, <a href="https://arxiv.org/format/astro-ph/0605206">other</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/10.1051/0004-6361:20054637">10.1051/0004-6361:20054637 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> On the geometrical evolution of the ionized gas in HII galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Cuisinier%2C+F">F. Cuisinier</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Telles%2C+E">E. Telles</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/0605206v1-abstract-short" style="display: inline;"> In this paper, we investigate the behaviour of the number of Lyman continuum ionizing photons as compared to the actual number of hydrogen recombinations in HII galaxies. We evaluate the number of ionizing photons from the population synthesis of spectra observed in the visible, extrapolating the spectra to the extreme ultraviolet (EUV), beyond the Lyman limit. We check for possible systematic… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0605206v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0605206v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0605206v1-abstract-full" style="display: none;"> In this paper, we investigate the behaviour of the number of Lyman continuum ionizing photons as compared to the actual number of hydrogen recombinations in HII galaxies. We evaluate the number of ionizing photons from the population synthesis of spectra observed in the visible, extrapolating the spectra to the extreme ultraviolet (EUV), beyond the Lyman limit. We check for possible systematic deviations of the predicted ionizing spectra in the EUV by comparing the ratio of the predicted number of ionizing photons to the number of recombinations, as measured in H$尾$, ${\rm 螖\log Q(H^0)}$, with the metallicity. We find that, as far as the number of ionizing photons is concerned, no systematic tendency can be detected. The ${\rm H尾}$ equivalent width can be understood as a nebular age indicator, decreasing with age, although the observed ${\rm H尾}$ equivalent width can also be affected by the contribution to the continuum by the accumulation of previous, non-ionizing stellar populations. We attribute the increase of ${\rm 螖\log Q(H^0)}$ with the age of the burst to the fact that more and more ionizing photons escape the nebulae when the nebulae get older, because of their increasing, expansion-induced subfragmentation. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0605206v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0605206v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 8 May, 2006; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2006. </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, accepted in A&A</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0406135">arXiv:astro-ph/0406135</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0406135">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0406135">ps</a>, <a href="https://arxiv.org/format/astro-ph/0406135">other</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/10.1086/422179">10.1086/422179 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Sub-Galactic Clumps at High Redshift: A Fragmentation Origin? </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Immeli%2C+A">Andreas Immeli</a>, <a href="/search/astro-ph?searchtype=author&query=Samland%2C+M">Markus Samland</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Gerhard%2C+O">Ortwin Gerhard</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="astro-ph/0406135v1-abstract-short" style="display: inline;"> We investigate the origin of the clumpy structures observed at high redshift, like the chain galaxies. We use a three dimensional chemodynamical simulation describing the dynamics of stars and a two-phase interstellar medium, as well as feedback processes from the stars. For high efficiency of energy dissipation in the cold cloud medium, the initially gaseous disk fragments and develops several… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0406135v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0406135v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0406135v1-abstract-full" style="display: none;"> We investigate the origin of the clumpy structures observed at high redshift, like the chain galaxies. We use a three dimensional chemodynamical simulation describing the dynamics of stars and a two-phase interstellar medium, as well as feedback processes from the stars. For high efficiency of energy dissipation in the cold cloud medium, the initially gaseous disk fragments and develops several massive clumps of gas and stars. We follow the evolution of the individual clumps and determine their masses, metallicities and velocities. A few dynamical times after fragmentation of the disk, the clumps merge to build a massive bulge. Calculating HST- and UBVRIJHKLM-colors, including absorption by interstellar dust, we determine the morphologies and colors of this model in HST images. Several peculiar morphological structures seen in the HDF can be well-explained by a fragmented galactic disk model, including chain galaxies and objects consisting of several nearby knots. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0406135v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0406135v1-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 June, 2004; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 2004. </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, Latex, 9 figures, to appear in the Astrophysical Journal. Version with high quality images available at http://www.astro.unibas.ch/leute/ai.shtml</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> Basel Preprint 143 </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astrophys.J. 611 (2004) 20-25 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0405265">arXiv:astro-ph/0405265</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0405265">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0405265">ps</a>, <a href="https://arxiv.org/format/astro-ph/0405265">other</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/10.1051/0004-6361:20048007">10.1051/0004-6361:20048007 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Stellar Populations in HII Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Cuisinier%2C+F">F. Cuisinier</a>, <a href="/search/astro-ph?searchtype=author&query=Telles%2C+E">E. Telles</a>, <a href="/search/astro-ph?searchtype=author&query=Kehrig%2C+C">C. Kehrig</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="astro-ph/0405265v1-abstract-short" style="display: inline;"> We analyse the stellar content of a large number of HII galaxies from the continua and absorption features of their spectra using population synthesis methods, in order to gain information about the star formation histories of these objects. We find that all galaxies of our sample contain an old stellar population (>= 1 Gyr) that dominates the stellar mass, and in a majority of these we also f… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0405265v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0405265v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0405265v1-abstract-full" style="display: none;"> We analyse the stellar content of a large number of HII galaxies from the continua and absorption features of their spectra using population synthesis methods, in order to gain information about the star formation histories of these objects. We find that all galaxies of our sample contain an old stellar population (>= 1 Gyr) that dominates the stellar mass, and in a majority of these we also found evidence for an intermediate-age population >= 50 Myr apart from the presently bursting, ionizing young generation <= 10^7 yrs <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0405265v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0405265v1-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 May, 2004; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 2004. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">23 pages, 14 Encapsulated Postscript figures, accepted for publication in A&A</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astron.Astrophys. 423 (2004) 133-146 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0312139">arXiv:astro-ph/0312139</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0312139">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0312139">ps</a>, <a href="https://arxiv.org/format/astro-ph/0312139">other</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/10.1051/0004-6361:20034282">10.1051/0004-6361:20034282 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Gas Physics, Disk Fragmentation, and Bulge Formation in Young Galaxies </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Immeli%2C+A">Andreas Immeli</a>, <a href="/search/astro-ph?searchtype=author&query=Samland%2C+M">Markus Samland</a>, <a href="/search/astro-ph?searchtype=author&query=Gerhard%2C+O">Ortwin Gerhard</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</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="astro-ph/0312139v1-abstract-short" style="display: inline;"> We investigate the evolution of star-forming gas-rich disks, using a 3D chemodynamical model including a dark halo, stars, and a two-phase interstellar medium with feedback processes from the stars. We show that galaxy evolution proceeds along very different routes depending on whether it is the gas disk or the stellar disk which first becomes unstable, as measured by the respective Q-parameters… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0312139v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0312139v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0312139v1-abstract-full" style="display: none;"> We investigate the evolution of star-forming gas-rich disks, using a 3D chemodynamical model including a dark halo, stars, and a two-phase interstellar medium with feedback processes from the stars. We show that galaxy evolution proceeds along very different routes depending on whether it is the gas disk or the stellar disk which first becomes unstable, as measured by the respective Q-parameters. This in turn depends on the uncertain efficiency of energy dissipation of the cold cloud component from which stars form. When the cold gas cools efficiently and drives the instability, the galactic disk fragments and forms a number of massive clumps of stars and gas. The clumps spiral to the center of the galaxy in a few dynamical times and merge there to form a central bulge component in a strong starburst. When the kinetic energy of the cold clouds is dissipated at a lower rate, stars form from the gas in a more quiescent mode, and an instability only sets in at later times, when the surface density of the stellar disk has grown sufficiently high. The system then forms a stellar bar, which channels gas into the center, evolves, and forms a bulge whose stars are the result of a more extended star formation history. We investigate the stability of the gas-stellar disks in both regimes, as well as the star formation rates and element enrichment. We study the morphology of the evolving disks, calculating spatially resolved colours from the distribution of stars in age and metallicity, including dust absorption. We then discuss morphological observations such as clumpy structures and chain galaxies at high redshift as possible signatures of fragmenting, gas-rich disks. Finally, we investigate abundance ratio distributions as a means to distinguish the different scenarios for bulge formation. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0312139v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0312139v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 4 December, 2003; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2003. </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, Latex, 14 figures, to appear in Astronomy and Astrophysics, Version with high quality images available at http://www.astro.unibas.ch/leute/ai.shtml</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> Basel Preprint 141 </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astron.Astrophys. 413 (2004) 547-561 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0203201">arXiv:astro-ph/0203201</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0203201">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0203201">ps</a>, <a href="https://arxiv.org/format/astro-ph/0203201">other</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/10.1051/0004-6361:20020446">10.1051/0004-6361:20020446 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Colour Evolution of Disk Galaxy Models from z=4 to z=0 </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">Pieter Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Samland%2C+M">Markus Samland</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">Roland Buser</a>, <a href="/search/astro-ph?searchtype=author&query=Gerhard%2C+O">Ortwin Gerhard</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="astro-ph/0203201v1-abstract-short" style="display: inline;"> We calculate synthetic UBVRIJHKLM images, integrated spectra and colours for the disk galaxy formation models of Samland & Gerhard (2002), from redshift z=4 to z=0. Two models are considered, an accretion model based on LambdaCDM structure formation simulations, and a classical collapse model in a dark matter halo. Both models provide the star formation history and dynamics of the baryonic compo… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0203201v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0203201v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0203201v1-abstract-full" style="display: none;"> We calculate synthetic UBVRIJHKLM images, integrated spectra and colours for the disk galaxy formation models of Samland & Gerhard (2002), from redshift z=4 to z=0. Two models are considered, an accretion model based on LambdaCDM structure formation simulations, and a classical collapse model in a dark matter halo. Both models provide the star formation history and dynamics of the baryonic component within a three-dimensional chemo-dynamical description. To convert to spectra and colours, we use the latest, metallicity-calibrated spectral library of Westera et al. (2002), including internal absorption. As a first application, we compare the derived colours with Hubble Deep Field North bulge colours and find good agreement. With our model, we disentangle metallicity effects and absorption effects on the integrated colours, and find that absorption effects are dominant for redshift z < 1.5. Furthermore, we confirm the quality of m_K as a mass tracer, and find indications for a correlation between (J-K) and metallicity gradients. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0203201v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0203201v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 13 March, 2002; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> March 2002. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">29 pages, LaTeX, 17 figures, revised version, submitted to A&A, a high resolution version can be found at http://www.astro.unibas.ch/leute/ms.shtml</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Report number:</span> Basel-report-135 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0112461">arXiv:astro-ph/0112461</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0112461">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0112461">ps</a>, <a href="https://arxiv.org/format/astro-ph/0112461">other</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/10.1023/A:1015552407031">10.1023/A:1015552407031 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> BaSeL: a library of synthetic spectra and colours for GAIA </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lastennet%2C+E">E. Lastennet</a>, <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">T. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Oblak%2C+E">E. Oblak</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/0112461v1-abstract-short" style="display: inline;"> The BaseL Stellar Library (BaSeL) is a library of synthetic spectra which has already been used in various astrophysical applications (stellar clusters studies, characterization and choice of the COROT potential targets, eclipsing binaries,...). This library could provide useful indications to 1) choose the best photometric system for the GAIA strategy by evaluating their expected performances a… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0112461v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0112461v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0112461v1-abstract-full" style="display: none;"> The BaseL Stellar Library (BaSeL) is a library of synthetic spectra which has already been used in various astrophysical applications (stellar clusters studies, characterization and choice of the COROT potential targets, eclipsing binaries,...). This library could provide useful indications to 1) choose the best photometric system for the GAIA strategy by evaluating their expected performances and 2) apply systematically the BaSeL models for any sample of GAIA targets. In this context, we describe one of the future developments of the BaSeL interactive web site to probe the GAIA photometric data: an automatic determination of atmospheric parameters from observed colours. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0112461v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0112461v1-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 December, 2001; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> December 2001. </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">to appear in Astrophysics and Space Science, proceedings "Census of the Galaxy: challenges for photometry and spectrometry with GAIA", eds. V. Vansevicius, A. Kucinskas and J. Sudzius</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astrophys.Space Sci. 280 (2002) 83-87 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/0110559">arXiv:astro-ph/0110559</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/0110559">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/0110559">ps</a>, <a href="https://arxiv.org/format/astro-ph/0110559">other</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/10.1051/0004-6361:20011493">10.1051/0004-6361:20011493 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> A standard stellar library for evolutionary synthesis. III. Metallicity calibration </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">T. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</a>, <a href="/search/astro-ph?searchtype=author&query=Cuisinier%2C+F">F. Cuisinier</a>, <a href="/search/astro-ph?searchtype=author&query=A.%2C+G+B">G. Bruzual A.</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="astro-ph/0110559v1-abstract-short" style="display: inline;"> We extend the colour calibration of the widely used BaSeL standard stellar library (Lejeune, Cuisinier, & Buser 1997, 1998) to non-solar metallicities, down to [Fe/H] ~ -2.0 dex. Surprisingly, we find that at the present epoch it is virtually impossible to establish a unique calibration of UBVRIJHKL colours in terms of stellar metallicity [Fe/H] which is consistent simultaneously with both colou… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0110559v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/0110559v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/0110559v1-abstract-full" style="display: none;"> We extend the colour calibration of the widely used BaSeL standard stellar library (Lejeune, Cuisinier, & Buser 1997, 1998) to non-solar metallicities, down to [Fe/H] ~ -2.0 dex. Surprisingly, we find that at the present epoch it is virtually impossible to establish a unique calibration of UBVRIJHKL colours in terms of stellar metallicity [Fe/H] which is consistent simultaneously with both colour-temperature relations and colour-absolute magnitude diagrams (CMDs) based on observed globular cluster photometry data and on published, currently popular standard stellar evolutionary tracks and isochrones. The problem appears to be related to the long-standing incompleteness in our understanding of convection in late-type stellar evolution, but is also due to a serious lack of relevant observational calibration data that would help resolve, or at least further significant progress towards resolving this issue. In view of the most important applications of the BaSeL library, we here propose two different metallicity calibration versions: (1) the "WLBC 99" library, which consistently matches empirical colour-temperature relations and which, therefore, should make an ideal tool for the study of individual stars; and (2), the "PADOVA 2000" library, which provides isochrones from the Padova 2000 grid (Girardi et al., 2000) that successfully reproduce Galactic globular-cluster colour-absolute magnitude diagrams and which thus should prove particularly useful for studies of collective phenomena in stellar populations in clusters and galaxies. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/0110559v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/0110559v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 25 October, 2001; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> October 2001. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">15 pages, LaTeX, documentclass aa, accepted for A and A</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/9906064">arXiv:astro-ph/9906064</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/9906064">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/9906064">ps</a>, <a href="https://arxiv.org/format/astro-ph/9906064">other</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> <p class="title is-5 mathjax"> Metallicity calibration of theoretical stellar SEDs using UBVRIJHKL photometry of globular clusters </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">Th. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/9906064v1-abstract-short" style="display: inline;"> Although stellar SED models are constantly improving and seem to show similar differential tendencies as measured spectra, their absolute properties (eg. absolute flux in different wavelength regions) can still differ significantly from the measured ones. Therefore, it is necessary to "color-calibrate" the theoretical spectra to obtain realistic model-based stellar spectra, which can then be use… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9906064v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/9906064v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/9906064v1-abstract-full" style="display: none;"> Although stellar SED models are constantly improving and seem to show similar differential tendencies as measured spectra, their absolute properties (eg. absolute flux in different wavelength regions) can still differ significantly from the measured ones. Therefore, it is necessary to "color-calibrate" the theoretical spectra to obtain realistic model-based stellar spectra, which can then be used for many purposes, such as population synthesis models. In order to calibrate a hybrid library (consisting of the Kurucz -, the Allard and Hauschild -, and the Scholz-models) of theoretical SEDs, UBVRIJHKLM photometric data of solar neighborhood stars were collected from the literature, and the solar metallicity models were calibrated using an algorithm developed by Cuisinier et. al. The corrections were then propagated through the whole grid of models, resulting in the "semi-empirical" models (available on ftp from the university of Basel). In order to extend the calibration to non-solar abundances, we have collected UBVRIJHKL photometric data from well-known Galactic globular clusters, covering a wide range of metallicities. We shall present first results, using the metallicity-calibrated library for calculating isochrones of metal-poor clusters. In particular, the observed slope and/or curvature of the RGB appears to be reproducible in a systematically correct manner for the first time. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9906064v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/9906064v1-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 June, 1999; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> June 1999. </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, 1 figure, to be published in the Annapolis Workshop on spetrophotometric dating of stars and galaxies proceedings</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/9905335">arXiv:astro-ph/9905335</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/9905335">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/9905335">ps</a>, <a href="https://arxiv.org/format/astro-ph/9905335">other</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> <p class="title is-5 mathjax"> Model atmosphere calibration for synthetic photometry applications: the uvby Stromgren photometric system </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">T. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Lastennet%2C+E">E. Lastennet</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/9905335v1-abstract-short" style="display: inline;"> In view of the importance of accurate fundamental stellar parameters for `Spectro-photometric dating of stars and galaxies", we present simultaneous effective temperature and metallicity determinations for a sample of 40 stars from Stromgren synthetic photometry with an empirically calibrated grid of model atmosphere spectra (BaSeL models). Comparisons with Ribas et al.'s (1998) results, using H… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9905335v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/9905335v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/9905335v1-abstract-full" style="display: none;"> In view of the importance of accurate fundamental stellar parameters for `Spectro-photometric dating of stars and galaxies", we present simultaneous effective temperature and metallicity determinations for a sample of 40 stars from Stromgren synthetic photometry with an empirically calibrated grid of model atmosphere spectra (BaSeL models). Comparisons with Ribas et al.'s (1998) results, using Hipparcos parallaxes, for 8 binaries of our working sample are presented, showing good agreement with the most reliable parallaxes, and giving hence a significant weight to the validity of the BaSeL models for synthetic photometry applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9905335v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/9905335v1-abstract-short').style.display = 'inline';">△ Less</a> </span> </p> <p class="is-size-7"><span class="has-text-black-bis has-text-weight-semibold">Submitted</span> 26 May, 1999; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> May 1999. </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, to appear in the PASP Conference Proceedings series of the Workshop "Spectrophotometric dating of stars and galaxies", Annapolis, Maryland (U.S.A.), eds. I. Hubeny, S. Heap, and R. Cornett</span> </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/9811146">arXiv:astro-ph/9811146</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/9811146">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/9811146">ps</a>, <a href="https://arxiv.org/format/astro-ph/9811146">other</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/10.1023/A:1002195323707">10.1023/A:1002195323707 <i class="fa fa-external-link" aria-hidden="true"></i></a></span> </div> </div> </div> <p class="title is-5 mathjax"> Simultaneous solutions of stellar parameters (Teff, [Fe/H]) from synthetic uvby Stromgren photometry </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lastennet%2C+E">E. Lastennet</a>, <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">T. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/9811146v1-abstract-short" style="display: inline;"> The comprehensive knowledge of fundamental parameters of single stars is the basis of the modelling of star clusters and galaxies. Most fundamental stellar parameters of the individual components in SB2 eclipsing binaries are known with very high accuracy. Unfortunately, while masses and radii are well determined, the temperatures strongly depend on photometric calibrations. In the present work,… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9811146v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/9811146v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/9811146v1-abstract-full" style="display: none;"> The comprehensive knowledge of fundamental parameters of single stars is the basis of the modelling of star clusters and galaxies. Most fundamental stellar parameters of the individual components in SB2 eclipsing binaries are known with very high accuracy. Unfortunately, while masses and radii are well determined, the temperatures strongly depend on photometric calibrations. In the present work, we have used an empirically-calibrated grid of theoretical stellar spectra (BaSeL models) for simultaneously deriving homogeneous effective temperatures and metallicities from observed data. For this purpose, we have selected 20 binary systems (40 stars) for which we have uvby Stromgren photometry with estimated errors (see Lastennet et al., astro-ph/9811103, for details). <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9811146v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/9811146v1-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 November, 1998; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 1998. </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">2 pages, LaTeX, 1 figure, uses crckapb.sty. To appear in the Proceedings of "Galaxy Evolution: Connecting the Distant Universe with the Local Fossil Record", ed. M. Spite. Organized by Paris-Meudon Observatory from 21-25 September, 1998 in Meudon (France)</span> </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Journal ref:</span> Astrophys.Space Sci. 265 (1999) 263-264 </p> </li> <li class="arxiv-result"> <div class="is-marginless"> <p class="list-title is-inline-block"><a href="https://arxiv.org/abs/astro-ph/9811103">arXiv:astro-ph/9811103</a> <span> [<a href="https://arxiv.org/pdf/astro-ph/9811103">pdf</a>, <a href="https://arxiv.org/ps/astro-ph/9811103">ps</a>, <a href="https://arxiv.org/format/astro-ph/9811103">other</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> <p class="title is-5 mathjax"> Metallicity-dependent effective temperature determination for eclipsing binaries from synthetic uvby Stromgren photometry </p> <p class="authors"> <span class="search-hit">Authors:</span> <a href="/search/astro-ph?searchtype=author&query=Lastennet%2C+E">E. Lastennet</a>, <a href="/search/astro-ph?searchtype=author&query=Lejeune%2C+T">T. Lejeune</a>, <a href="/search/astro-ph?searchtype=author&query=Westera%2C+P">P. Westera</a>, <a href="/search/astro-ph?searchtype=author&query=Buser%2C+R">R. Buser</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="astro-ph/9811103v1-abstract-short" style="display: inline;"> Stromgren synthetic photometry from an empirically calibrated grid of stellar atmosphere models has been used to derive the effective temperature of each component of double lined spectroscopic (SB2) eclipsing binaries. For this purpose, we have selected a sub-sample of 20 SB2s for which b-y, m_1, and c_1 individual indices are available. This new determination of effective temperature has been… <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9811103v1-abstract-full').style.display = 'inline'; document.getElementById('astro-ph/9811103v1-abstract-short').style.display = 'none';">▽ More</a> </span> <span class="abstract-full has-text-grey-dark mathjax" id="astro-ph/9811103v1-abstract-full" style="display: none;"> Stromgren synthetic photometry from an empirically calibrated grid of stellar atmosphere models has been used to derive the effective temperature of each component of double lined spectroscopic (SB2) eclipsing binaries. For this purpose, we have selected a sub-sample of 20 SB2s for which b-y, m_1, and c_1 individual indices are available. This new determination of effective temperature has been performed in a homogeneous way for all these stars. As the effective temperature determination is related to the assumed metallicity, we explore simultaneous solutions in the (Teff,[Fe/H])-plane and present our results as confidence regions computed to match the observed values of surface gravity, b-y, m_1, and c_1, taking into account interstellar reddening. These confidence regions show that previous estimates of Teff are often too optimistic, and that [Fe/H] should not be neglected in such determinations. Comparisons with Ribas et al. (1998) using Hipparcos parallaxes are also presented for 8 binaries of our working sample, showing good agreement with the most reliable parallaxes. This point gives a significant weight to the validity of the BaSeL models for synthetic photometry applications. <a class="is-size-7" style="white-space: nowrap;" onclick="document.getElementById('astro-ph/9811103v1-abstract-full').style.display = 'none'; document.getElementById('astro-ph/9811103v1-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 November, 1998; <span class="has-text-black-bis has-text-weight-semibold">originally announced</span> November 1998. </p> <p class="comments is-size-7"> <span class="has-text-black-bis has-text-weight-semibold">Comments:</span> <span class="has-text-grey-dark mathjax">Accepted for publication in A&A, 11 pages, LaTeX, 48 figures</span> </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 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