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

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Context. While most (if not all) Type I Galactic globular clusters (GGCs) are characterised by spreads in the abundances of light chemical elements (e.g. Li, N, O, Na, Mg, Al), it is not yet well established whether similar spreads may…

Astrophysics of Galaxies · Physics 2021-12-08 V. Dobrovolskas , E. Kolomiecas , A. Kučinskas , J. Klevas , S. Korotin

We determined abundances of Mg and K in the atmospheres of 53 (Mg) and 75 (K) turn-off (TO) stars of the Galactic globular cluster 47 Tuc. The obtained abundances, together with those of Li, O, and Na, were used to search for possible…

Solar and Stellar Astrophysics · Physics 2018-04-27 A. Černiauskas , A. Kučinskas , J. Klevas , V. Dobrovolskas , S. Korotin , P. Bonifacio , H. -G. Ludwig , E. Caffau , M. Steffen

We present the results of determination of the age, helium mass fraction (Y) in terms of the used stellar evolutionary models, metallicity ([Fe/H]), and abundances of the elements C, O, Na, Mg, Ca, Ti, Cr and Mn for 26 globular clusters of…

Astrophysics of Galaxies · Physics 2020-09-07 M. E. Sharina , V. V. Shimansky , N. N. Shimanskaya

We outline a method to measure the detailed chemical composition of extragalactic (unresolved) globular clusters (GCs) from echelle spectra of their integrated light. Our goal is to use this method to measure abundance patterns of GCs in…

Astrophysics · Physics 2007-05-23 R. A. Bernstein , A. McWilliam

Long-slit medium-resolution spectra of the Galactic globular clusters (GCs) NGC6229 and NGC6779, obtained with the CARELEC spectrograph at the 1.93-m telescope of the Haute-Provence observatory, have been used to determine the age, helium…

Solar and Stellar Astrophysics · Physics 2015-09-15 Khamidullina D. A. , Sharina M. E. , Shimansky V. V. , Davoust E

High signal-to-noise integrated spectra of the metal-rich globular cluster 47 Tuc, spanning the H-gamma(HR) and Fe4668 line indices, have been obtained. The combination of these indices has been suggested (Jones & Worthey 1995, ApJ, 446,…

We investigate possible relations between the abundances of zinc and the light elements sodium, magnesium, and potassium in the atmospheres ofred giant branch (RGB) stars of the Galactic globular cluster 47~Tuc and study connections between…

Solar and Stellar Astrophysics · Physics 2018-06-11 A. Černiauskas , A. Kučinskas , J. Klevas , P. Bonifacio , H. -G. Ludwig , E. Caffau , M. Steffen

It is widely accepted that individual Galactic globular clusters harbor two coeval generations of stars, the first one born with the `standard' alpha-enhanced metal mixture observed in field Halo objects, the second one characterized by an…

Astrophysics of Galaxies · Physics 2012-03-21 Paula Coelho , Susan Percival , Maurizio Salaris

Chemical abundances are presented for 25 M31 globular clusters (GCs), based on moderately high resolution (R = 22, 500) H-band integrated light spectra from the Apache Point Observatory Galactic Evolution Experiment (APOGEE). Infrared…

We present a new method for the determination of [Fe/H] for globular clusters. This new method is based on moderate resolution (R~1500) near-IR spectroscopy in the K-band of 6 to 10 of the brightest giants in a cluster. Our calibration is…

Astrophysics · Physics 2009-11-06 J. A. Frogel , A. W. Stephens , S. Ramirez , D. L. DePoy

We report the first detailed chemical abundances for 5 globular clusters (GCs) in M31 from high-resolution (R ~ 25,000) spectroscopy of their integrated light. These GCs are the first in a larger set of clusters observed as part of an…

Astrophysics of Galaxies · Physics 2015-05-14 J. E. Colucci , R. A. Bernstein , S. Cameron , A. McWilliam , J. G. Cohen

This paper presents the results of analysing the integrated light (IL) low-resolution spectra of globular clusters (GCs) in the M31 and Centaurus A groups of galaxies. The sample consists of eight very metal-poor GCs ($\rm [Fe/H]\le -2$…

Astrophysics of Galaxies · Physics 2025-12-10 M. E. Sharina , M. I. Maricheva , A. Y. Kniazev , V. V. Shimansky , I. A. Acharova

aims: Our aim is to determine Li abundances in TO stars of the Globular Cluster 47 Tuc and test theories about Li variations among TO stars. method: We make use of high resolution (R~ 43000), high signal-to-noise ratio (S/N=50--70) spectra…

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

We define a method for analysis of the integrated spectra of extra-galactic globular clusters that provides more reliable measures of age, metallicity and alpha-element abundance ratio than have so far been achieved. The method involves the…

Astrophysics · Physics 2009-11-10 Robert N. Proctor , Duncan A. Forbes , Michael A. Beasley

We present a comparison of high-resolution, integrated-light, detailed chemical abundances for Galactic and extragalactic globular clusters in both massive galaxies and dwarf galaxies. We include measurements of Fe, Ca, Si, Na, and Al for…

Cosmology and Nongalactic Astrophysics · Physics 2013-02-27 J. E. Colucci , R. A. Bernstein , A. McWilliam , J. G. Cohen

We present chemical abundances of Al and several Fe-Peak and neutron-capture elements for 13 red giant branch stars in the Galactic globular cluster NGC 6171 (M107). The abundances were determined using equivalent width and spectrum…

Solar and Stellar Astrophysics · Physics 2015-05-30 Julia E. O'Connell , Christian I. Johnson , Catherine A. Pilachowski , Geoffrey Burks

We report on a strictly differential line-by-line analysis of high quality UVES spectra of bright giants in the metal-poor globular cluster NGC 6752. We achieved high precision differential chemical abundance measurements for Fe, Na, Si,…

We determined zirconium abundance in the atmospheres of 327 red giant branch (RGB) stars in the globular cluster 47 Tuc. The 1D LTE abundances were obtained from the archival VLT GIRAFFE spectra, using 1D hydrostatic ATLAS9 stellar model…

Solar and Stellar Astrophysics · Physics 2020-03-18 Edgaras Kolomiecas , Vidas Dobrovolskas , Arūnas Kučinskas

Large star-to-star abundance variations are direct evidence of multiple stellar populations in Galactic globular clusters (GCs). The main and most widespread chemical signature is the anti-correlation of the stellar Na and O abundances. The…

Solar and Stellar Astrophysics · Physics 2019-04-10 Eugenio Carretta