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Related papers: Towards a Solution for the Ca II Triplet Puzzle : …

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We present kinematics and stellar population properties of 17 dwarf early-type galaxies in the luminosity range -14> M_B> -19. Our sample fills the gap between the intensively studied giant elliptical and Local Group dwarf spheroidal…

Astrophysics · Physics 2009-11-07 D. Thomas , R. Bender , U. Hopp , C. Maraston , L. Greggio

Stellar metallicity gradients in the outer regions of galaxies are a critical tool for disentangling the contributions of in-situ and ex-situ formed stars. In the two-phase galaxy formation scenario, the initial gas collapse creates steep…

The NIR Ca II triplet absorption lines have proven to be an important tool for quantitative spectroscopy of individual red giant branch stars in the Local Group, providing a better understanding of metallicities of stars in the Milky Way…

We present an extensive catalog of 5405 early-type dwarf (dE) galaxies located in the various environments, i.e., clusters, groups and fields, of the local universe ($z$ $<$ 0.01). The dEs are selected through visual inspection of the…

Based on high-resolution spectra obtained during gravitational microlensing events we present a detailed elemental abundance analysis of 32 dwarf and subgiant stars in the Galactic bulge. [ABRIDGED], we now have 58 microlensed bulge dwarfs…

Dwarf ellipticals are the most common galaxy type in cluster environments, however the challenges associated with their observation mean their formation mechanisms are still poorly understood. To address this, we present deep integral field…

We present seven new abundance measurements of the elements O, C and Si at z > 4.5, doubling the existing sample of weakly depleted elements in gas-rich galaxies, in order to constrain the first ~1 billion years of cosmic metal evolution.…

Astrophysics of Galaxies · Physics 2020-01-08 Suraj Poudel , Varsha P. Kulkarni , Frances H. Cashman , Brenda Frye , Celine Peroux , Hadi Rahmani , Samuel Quiret

We use previously-published moderate-resolution spectra in combination with stellar atmosphere models to derive the first measured chemical abundance ratios in the Leo II dSph galaxy. We find that for spectra with SNR > 24, we are able to…

Astrophysics · Physics 2009-11-13 Matthew Shetrone , Michael H. Siegel , David O. Cook , Tammy Bosler

We present a new version of the compiled catalogue of nearby stars for which was published the spectoscopically determined effective temperatures, surface gravities, and abundances of iron, magnesium, calcium, silicon, and titanium.…

Astrophysics · Physics 2007-10-25 T. V. Borkova , M. S. Katchieva , B. A. Marsakov , D. M. Pitkina

The Small Magellanic Cloud (SMC) is the only dwarf galaxy in the Local Group known to have formed and preserved populous star clusters continuously over the past 12 Gyr. These clusters provide a unique, closely spaced set of single-age,…

Astrophysics · Physics 2007-05-23 A. Kayser , E. K. Grebel , D. R. Harbeck , A. A. Cole , A. Koch , J. S. Gallagher , G. S. Da Costa

We present an unbiased method for evaluating the ranges of ages and metallicities which are allowed by the photometric properties of the stellar populations that dominate the light of early-type galaxies in clusters. The method is based on…

Astrophysics · Physics 2009-10-30 I. Ferreras , S. Charlot , J. Silk

Abridged Abstract - Utilizing the FORS2 instrument on the VLT, we have obtained near infrared spectra for more than 200 stars in 28 populous LMC clusters. This cluster sample spans a large range of ages (~ 1-13 Gyr) and metallicities (-0.3…

Astrophysics · Physics 2008-11-26 A. J. Grocholski , A. A. Cole , A. Sarajedini , D. Geisler , V. V. Smith

For the first time we show the detailed late-stage chemical evolution history of small nearby dwarf spheroidal galaxy in the Local Group. We present the results of a high resolution (R$\sim$20000) FLAMES/GIRAFFE abundance study at ESO/VLT…

We present a study of internal stellar population gradients in early-type cluster galaxies. Using the VLT VIMOS integral field unit, we observed 19 galaxies in the core of the Shapley Supercluster (z = 0.048). The radial trends in nine…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 T. D. Rawle , Russell J. Smith , J. R. Lucey

Li abundances are derived for a sample of bulgelike stars with isochronal ages of 10-11 Gyr. These stars have orbits with pericentric distances, Rp, as small as 2-3 kpc and Zmax < 1 kpc. The sample comprises G and K dwarf stars in the…

Astrophysics · Physics 2009-11-07 Luciana Pompeia , Beatriz Barbuy , Michel Grenon , Bruno Castilho

We present the stellar metallicities and multi-element abundances (C, Mg, Si, Ca, Ti, Cr, and Fe) of 15 massive (log $M/M_\odot=10.2-11.2$) quiescent galaxies at z=1-3, derived from ultradeep JWST-SUSPENSE spectra. Compared to quiescent…

We compute new population synthesis models of Lick absorption line indices with variable alpha/Fe ratios and use them to derive average ages, metallicities, and alpha/Fe element enhancements for a sample of 126 field and cluster early-type…

Astrophysics · Physics 2007-05-23 Daniel Thomas , Claudia Maraston , Ralf Bender

New observations of 16 dwarf elliptical galaxies in the Virgo Cluster indicate that at least seven dEs have significant velocity gradients along their optical major axis, with typical rotation amplitudes of 20-30 km/s. Of the remaining nine…

Astrophysics · Physics 2009-11-10 L. van Zee , E. D. Skillman , M. P. Haynes

In this paper we study the underlying stellar population of a sample of 65 nearby early-type galaxies predominantly located in low density environments. Ages, metallicities and [alpha/Fe] ratios have been derived through the comparison of…

Astrophysics · Physics 2010-10-28 F. Annibali , A. Bressan , R. Rampazzo , W. W. Zeilinger , L. Danese

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…

Astrophysics · Physics 2008-11-26 Thorsten Lisker , Katharina Glatt , Pieter Westera , Eva K. Grebel
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