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Related papers: Globular Cluster Abundances from High-Resolution I…

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Context: The combination of optical and near-infrared (NIR) colours has the potential to break the age/metallicity degeneracy and offers a better metallicity sensitivity than optical colours alone. Previous studies of extragalactic globular…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 A. L. Chies-Santos , S. S. Larsen , E. M. Wehner , H. Kuntschner , J. Strader , J. P. Brodie

We present abundance ratios for 23 elements with respect to Fe in a sample of stars with a wide range in luminosity, from luminous giants to stars near the turnoff, in the globular cluster M71. The analyzed spectra, obtained with HIRES at…

Astrophysics · Physics 2009-11-07 Solange V. Ramirez , Judith G. Cohen

We present CH and CN index analysis and C and N abundance calculations based on the low-resolution blue spectra of red giant branch (RGB) stars in the Galactic globular cluster NGC 7089 (M 2). Our main goal is to investigate the C-N…

Solar and Stellar Astrophysics · Physics 2015-06-11 C. Lardo , E. Pancino , A Mucciarelli , A. P. Milone

We present LTE chemical abundances for five red giants and one AGB star in the Galactic globular cluster (GC) M5 based on high resolution spectroscopy using the MIKE spectrograph on the Magellan 6.5-m Clay telescope. Our results are based…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas Koch , Andrew McWilliam

We describe a new method for determining total gas-phase abundances for the Galactic ISM with minimal ionization uncertainties. For sight lines toward globular clusters containing both UV-bright stars and radio pulsars, one can measure…

Astrophysics · Physics 2009-11-13 J. Christopher Howk , Kenneth R. Sembach , Blair D. Savage

We have carried out a detailed abundance analysis for 21 elements in a sample of 25 stars with a wide range in luminosity from luminous giants to stars near the main sequence turnoff in the globular cluster M13 and in a sample of 13 stars…

Astrophysics · Physics 2009-10-12 Judith G. Cohen , Jorge Melendez

Context: M 75 is a relatively young Globular Cluster (GC) found at 15 kpc from the Galactic centre at the transition region between the inner and outer Milky Way halos. Aims: Our aims are to perform a comprehensive abundance study of a…

Astrophysics of Galaxies · Physics 2015-06-15 Nikolay Kacharov , Andreas Koch , Andrew McWilliam

Globular Clusters (GCs) in the Milky Way are the primary laboratories for establishing the ages of the oldest stellar populations and for measuring the color-magnitude relation of stars. In infrared (IR) color-magnitude diagrams (CMDs), the…

Solar and Stellar Astrophysics · Physics 2016-05-25 Matteo Correnti , Mario Gennaro , Jason S. Kalirai , Thomas M. Brown , Annalisa Calamida

By using the multifiber spectrograph FLAMES mounted at the ESO-VLT, we have obtained high-resolution spectra for 18 giant stars, belonging to 3 old globular clusters of the Large Magellanic Cloud (namely NGC 1786, 2210 and 2257). While…

Solar and Stellar Astrophysics · Physics 2009-11-13 A. Mucciarelli , L. Origlia , F. R. Ferraro , E. Pancino

We present [Fe/H], ages, and Ca abundances for an initial sample of 10 globular clusters in NGC 5128 obtained from high resolution, high signal-to-noise ratio echelle spectra of their integrated light. All abundances and ages are obtained…

Astrophysics of Galaxies · Physics 2015-06-16 J. E. Colucci , M. F. Duran , R. A. Bernstein , A. McWilliam

We present a chemical composition analysis of 36 giants in the nearby mildy metal-poor (<[Fe/H]> = -1.18) "CN-bimodal" globular cluster M4. Confronted with a cluster that has large and variable interstellar extinction across the cluster…

We use photometric and spectroscopic observations of the eclipsing binary E32 in the globular cluster 47 Tuc to derive the masses, radii, and luminosities of the component stars. The system has an orbital period of 40.9 d, a markedly…

Here we aim to understand the origin of 47 Tuc's La-rich star Lee 4710. We report abundances for O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Co, Ni, Zn, Y, Zr, Ba, La, Ce, Pr, Nd, and Eu, and present a detailed abundance analysis of two 47 Tuc…

Solar and Stellar Astrophysics · Physics 2015-08-06 M. J. Cordero , C. J. Hansen , C. I. Johnson , C. A. Pilachowski

We present a new library of integrated spectra of 40 Galactic globular clusters, obtained with the Blanco 4-m telescope and the R-C spectrograph at the Cerro Tololo Interamerican Observatory. The spectra cover the range ~ 3350 -- 6430 A…

Astrophysics · Physics 2009-11-11 Ricardo P. Schiavon , James A. Rose , Stephane Courteau , Lauren A. MacArthur

We develop a new set of models for intermediate-metallicity single stellar populations in the blue/optical region and use those models to determine the spectroscopic age of 47 Tuc. The models are based on a moderately high-resolution (1.8 A…

Astrophysics · Physics 2009-11-07 Ricardo P. Schiavon , S. M. Faber , James A. Rose , Bruno V. Castilho

For decades, it has been theorized that a tenuous but detectable intracluster medium should be present in globular clusters, which is continuously replenished by the gas and dust ejected by bright giants and periodically cleared by…

Stellar models for -2.5 <= [Fe/H] <= -0.5 that have been computed for variations in the C:N:O abundance ratio (for two different values of [CNO/Fe]) are compared with HST Wide Field Camera 3 (WFC3) observations of the globular clusters…

Solar and Stellar Astrophysics · Physics 2021-12-15 Don A. VandenBerg , Luca Casagrande , Bengt Edvardsson

We have previously reported on chemical abundance trends with evolutionary state in the globular cluster NGC 6397 discovered in analyses of spectra taken with FLAMES at the VLT. Here, we reinvestigate the FLAMES-UVES sample of 18 stars,…

Solar and Stellar Astrophysics · Physics 2012-09-24 T. Nordlander , A. J. Korn , O. Richard , K. Lind

The light elements Li, O, Na, Al, and Mg are known to show star to star variations in the globular clusters 47 Tuc and NGC 6752. Such variations are interpreted as due to processing in a previous generation of stars. In this paper we…

Astrophysics of Galaxies · Physics 2015-05-13 L. Sbordone , M. Limongi , A. Chieffi , E. Caffau , H. -G. Ludwig , P. Bonifacio

Context. Open clusters are ideal test particles to study the chemical evolution of the Galactic disc. However the existing high-resolution abundance determinations, not only of [Fe/H], but also of other key elements, is largely insufficient…

Astrophysics of Galaxies · Physics 2015-05-28 R. Carrera , E. Pancino