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Related papers: Metallicity variations in the Type II globular clu…

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We present the chemical composition of 206 red giant branch stars members of the Small Magellanic Cloud (SMC) using optical, high-resolution spectra collected with the multi-object spectrograph FLAMES-GIRAFFE at the ESO Very Large…

Astrophysics of Galaxies · Physics 2023-03-29 A. Mucciarelli , A. Minelli , M. Bellazzini , C. Lardo , D. Romano , L. Origlia , F. R. Ferraro

Studies during the last decade have revealed that nearly all Globular Clusters (GCs) host multiple populations (MPs) of stars with a distinctive chemical patterns in light elements. No evidence of such MPs has been found so far in…

Astrophysics of Galaxies · Physics 2016-05-25 I. Cabrera-Ziri , C. Lardo , B. Davies , N. Bastian , G. Beccari , S. S. Larsen , S. Hernandez

The very metal-poor star HE 0338-3945 shows a double-enhanced pattern of the neutron-capture elements. The study to this sample could make people gain a better understanding of s- and r-process nucleosynthesis at low metallicity. Using a…

Solar and Stellar Astrophysics · Physics 2010-10-22 Wenyuan Cui , Jiang Zhang , Zizhong Zhu , Bo Zhang

Spectroscopic observations of 32 HII regions in the spiral galaxy NGC 3963 and the barred irregular galaxy NGC 7292 were carried out with the 2.5-m telescope of the Caucasus Mountain Observatory of the Sternberg Astronomical Institute using…

Astrophysics of Galaxies · Physics 2021-05-25 Alexander S. Gusev , Alexander V. Dodin

We present the results of the first analysis of high dispersion spectra of four red HB stars in the metal rich globular cluster NGC 6528, located in Baade's Window. We find that the mean [Fe/H] for NGC 6528 is +0.07+-0.01 dex (error of the…

Astrophysics · Physics 2009-11-06 Eugenio Carretta , Judith G. Cohen , Raffaele G. Gratton , Bradford B. Behr

We present a detailed chemical composition analysis of 35 red giant stars in the globular cluster M22. High resolution spectra for this study were obtained at five observatories, and analyzed in a uniform manner. We have determined…

We observed a sample of 90 red giant branch (RGB) stars in NGC 2808 using FLAMES/GIRAFFE and the high resolution grating with the set up HR21. These stars have previous accurate atmospheric parameters and abundances of light elements. We…

Solar and Stellar Astrophysics · Physics 2018-07-11 Eugenio Carretta , Angela Bragaglia , Sara Lucatello , Raffaele G. Gratton , Valentina D'Orazi , Antonio Sollima

We present detailed chemical compositions of 10 red giant star members of the Galactic (open) cluster NGC 752, derived from high-resolution (R $\approx$ 60,000), high signal-to-noise ($S/N$ $\geq$ 140) spectra. We confirmed cluster…

Solar and Stellar Astrophysics · Physics 2015-06-23 G. Böcek Topcu , M. Afşar , M. Schaeuble , C. Sneden

New near-infrared observations of NGC6528 are presented. The JHK observations complement a previous HST/NICMOS data set by Ortolani et al. (2001), in that they sample a larger area, contain a more numerous sample of red giant stars, and…

Astrophysics · Physics 2009-11-07 Y. Momany , S. Ortolani , E. V. Held , B. Barbuy , E. Bica , A. Renzini , L. R. Bedin , R. M. Rich , G. Marconi

We have observed high-dispersion echelle spectra of red giant members in the five open clusters NGC 1342, NGC 1662, NGC 1912, NGC 2354 and NGC 2447 and determined their radial velocities and chemical compositions. These are the first…

Solar and Stellar Astrophysics · Physics 2015-06-17 Arumalla B. S. Reddy , Sunetra Giridhar , David L. Lambert

Thanks to the large amount of spectroscopic and photometric data assembled in the last couple of decades, the assumption that all globular clusters (GCs) contain a simple mono-metallic stellar population has been modified. Besides the…

Solar and Stellar Astrophysics · Physics 2013-02-12 A. F. Marino

We present a photometric and spectroscopic study of multiple populations along the asymptotic-giant branch (AGB) of the intermediate-metallicity globular clusters (GCs) NGC2808 and NGC6121 (M4). Chemical abundances of O, Na, Mg, Al, Si, Ca,…

Solar and Stellar Astrophysics · Physics 2019-10-09 A. F. Marino , A. P. Milone , D. Yong , G. Da Costa , M. Asplund , L. R. Bedin , H. Jerjen , D. Nardiello , G. Piotto , A. Renzini , M. Shetrone

Mg isotopic abundance ratios are measured in 20 bright red giants in globular cluster NGC 6752 based on very high-resolution, high signal-to-noise spectra obtained with UVES on the VLT. There is a considerable spread in the ratio…

Astrophysics · Physics 2009-11-07 David Yong , Frank Grundahl , David L. Lambert , Poul Erik Nissen , Matthew Shetrone

Among stars in Galactic globular clusters the carbon abundance tends to decrease with increasing luminosity on the upper red giant branch, particularly within the lowest metallicity clusters. While such a phenomena is not predicted by…

Solar and Stellar Astrophysics · Physics 2019-04-08 Jeffrey M. Gerber , Michael M. Briley , Graeme H. Smith

We study the distribution of aluminum abundances among red giants in the peculiar globular cluster NGC 1851. Aluminum abundances were derived from the strong doublet Al I 8772-8773 A measured on intermediate resolution FLAMES spectra of 50…

Astrophysics of Galaxies · Physics 2015-06-05 Eugenio Carretta , Valentina D'Orazi , Raffaele G. Gratton , Sara Lucatello

We have made observations with the Keck I telescope and HIRES at a resolution of $\sim$45,000 of five nearly identical stars at the turn-off of the metal-rich globular cluster M 71. Our mean Fe abundance, [Fe/H]=-0.80 +-0.02, is in…

We present abundances of globular clusters in the Milky Way and Fornax from integrated light spectra. Our goal is to evaluate the consistency of the integrated light analysis relative to standard abundance analysis for individual stars in…

Astrophysics of Galaxies · Physics 2017-01-11 J. E. Colucci , R. A. Bernstein , A. McWilliam

We present an abundance analysis of 101 subgiant branch (SGB) stars in the globular cluster M22. Using low resolution FLAMES/GIRAFFE spectra we have determined abundances of the neutron-capture strontium and barium and the light element…

We have performed a detailed abundance analysis of 10 red giant members of the heavily obscured bulge globular cluster HP~1 using high-resolution, high S/N near-infrared spectra collected with the Apache Point Observatory Galactic Evolution…

Astrophysics of Galaxies · Physics 2025-04-16 Lady Henao , Sandro Villanova , Doug Geisler , José G. Fernández-Trincado

We recently discovered that NGC 3201 has characteristics that set it outside the current twofold classification scheme for Galactic globular clusters (GCs). Most GCs are mono-metallic and show light-element abundance variations (e.g., Na-O…

Solar and Stellar Astrophysics · Physics 2020-03-18 Bruno Dias , Ignacio Araya , João Paulo Nogueira-Cavalcante , Leila Saker , Ahmed Shokry