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Related papers: The Age, Metallicity and Alpha-Element Abundance o…

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In this second paper of a series on the accuracy and precision of the determination of age and metallicity of simple stellar populations (SSPs) by means of the full spectrum fitting technique, we study the influence of star cluster mass…

Astrophysics of Galaxies · Physics 2021-01-11 Paul Goudfrooij , Randa Asa'd

We present a study of the metallicity and age of the globular clusters system of M49 (NGC 4472), the most luminous galaxy in the Virgo cluster. We measure Lick indices for 47 GCs in M49 from LRIS/Keck spectra and establish their metallicity…

Astrophysics · Physics 2009-11-07 Judith G. Cohen , J. P. Blakeslee , P. Cote

We are using full spectrum fitting to determine the ages and metallicities of Galactic clusters (M67 and globular clusters). We find that the method is very accurate to measure the metallicity. Blue horizontal branches are well identified…

Astrophysics · Physics 2009-11-13 Mina Koleva , Philippe Prugniel , Pierre Ocvirk , Damien Le Borgne

Ages have been derived for 55 globular clusters (GCs) from overlays of isochrones onto the turnoff photometry, assuming distances based on fits of zero-age horizontal branch (ZAHB) models to the lower bound of the observed distributions of…

Astrophysics of Galaxies · Physics 2013-10-14 Don A. Vandenberg , Karsten Brogaard , Ryan Leaman , Luca Casagrande

We present a new library of semi-empirical stellar population models that are based on the empirical MILES and semi-empirical sMILES stellar libraries. The models span a large range of age and metallicity, in addition to an [$\alpha$/Fe]…

Astrophysics of Galaxies · Physics 2023-06-12 Adam T. Knowles , Anne E. Sansom , Alex Vazdekis , Carlos Allende Prieto

We present line-strength gradients for 22 spectral indices measured in a sample of 82 early-type galaxies in different environments,including the high-density core of the Coma cluster, the Virgo cluster,poor groups,and field galaxies. We…

Astrophysics · Physics 2009-11-11 P. Sanchez-Blazquez , J. Gorgas , N. Cardiel

The last decade has seen a revolution in our knowledge of the Galaxy thanks to the Gaia and asteroseismic space missions and the ground-based spectroscopic surveys. To complete this picture, it is necessary to map the ages of its stellar…

We present measurements of ages, metallicities, and [alpha/Fe] ratios for 16 globular clusters (GC) in NGC 147, NGC 185, and NGC 205 and of the central regions of the diffuse galaxy light in NGC 185, and NGC 205. Our results are based on…

Astrophysics · Physics 2009-11-11 M. E. Sharina , V. L. Afanasiev , T. H. Puzia

We present an astrometry and photometry catalogue of globular cluster (GC) candidates detected with HST WFPC2 in a sample of 19 early-type galaxies, appropriate for comparison to the low-mass X-ray binary (LMXB) populations observed with…

Astrophysics · Physics 2008-12-18 Philip J Humphrey

We present radial stellar population parameters for a subsample of 12 galaxies from the 36 isolated early-type galaxies of Reda et al. Using new long-slit spectra, central values and radial gradients for the stellar age, metallicity [Z/H]…

We present detailed abundance measurements for 45 globular clusters (GCs) in galaxies in (and, in one case, beyond) the Local Group. The measurements are based on new high-resolution integrated-light spectra of GCs in NGC 185, NGC 205, M31,…

Astrophysics of Galaxies · Physics 2022-04-20 S. S. Larsen , P. Eitner , E. Magg , M. Bergemann , C. A. S. Moltzer , J. P. Brodie , A. J. Romanowsky , J. Strader

We present results derived from VLT-FORS2 spectra of 17 globular clusters associated with the nearby lenticular galaxy NGC3115. Comparing line-strength indices to new stellar population models by Thomas et al. we determine ages,…

Astrophysics · Physics 2007-05-23 Harald Kuntschner , Bodo L. Ziegler , R. M. Sharples , Guy Worthey , Klaus J. Fricke

Using data from the GALAH survey, we explore the dependence of elemental abundances on stellar age and metallicity among Galactic disc stars. We find that the abundance of most elements can be predicted from age and [Fe/H] with an intrinsic…

We have extended our evolutionary synthesis code, GALEV, to include Lick/IDS absorption-line indices for both simple and composite stellar population models (star clusters and galaxies), using the polynomial fitting functions of Worthey et…

Astrophysics · Physics 2009-11-11 Thomas Lilly , Uta Fritze-v. Alvensleben

In this paper we refine our method for the abundance analysis of high resolution spectroscopy of the integrated light of unresolved globular clusters (GCs). This method was previously demonstrated for the analysis of old ($>$10 Gyr) Milky…

Astrophysics of Galaxies · Physics 2015-05-27 J. E. Colucci , R. A. Bernstein , S. A. Cameron , A. McWilliam

The presence of Multiple Stellar Populations (MSPs) in Galactic Globular Clusters (GCs) is a poorly understood phenomenon. By probing different spectral ranges that are affected by different absorption lines using the multi-band photometric…

We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic globular clusters', to identify and characterize their…

We present metallicity measurements based on GIRAFFE@VLT spectra of 80 subgiant-branch stars of the Galactic globular cluster Omega Centauri. The VLT spectroscopic data are complemented by ACS/HST and [email protected] high-accuracy…

We have obtained high-res, high S/N ratio CCD echelle spectra of 10 bright red giants in 3 GCs (47Tuc, NGC6752 and NGC6397) roughly spanning the range of metallicities of the galactic GC system; they reveal no evidence of star to star…

Astrophysics · Physics 2009-07-28 E. Carretta , R. G. Gratton

Spectrophotometric indices for $18$ Galactic globular clusters, obtained from CCD observations and careful reductions, were used to determine reliable calibrations on metallicity $[Fe/H]$. The indices were measured in the bandpasses adopted…

Astrophysics · Physics 2016-08-30 S. Covino , S. Galletti , L. E. Pasinetti
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