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Related papers: A spectroscopic study of the Globular Cluster NGC …

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Recent work has shown that most globular clusters have at least two chemically distinct components, as well as cluster-to-cluster differences in the mean [O/Fe], [Mg/Fe], and [Si/Fe] ratios at similar [Fe/H] values. In order to investigate…

Solar and Stellar Astrophysics · Physics 2015-06-05 Don A. VandenBerg , Peter A. Bergbusch , Aaron Dotter , Jason W. Ferguson , Georges Michaud , Jacques Richer , Charles Proffitt

We present the first measure of Fe and Na abundances in NGC 6362, a low-mass globular cluster where first and second generation stars are fully spatially mixed. A total of 160 member stars (along the red giant branch and the red horizontal…

Solar and Stellar Astrophysics · Physics 2016-06-22 A. Mucciarelli , E. Dalessandro , D. Massari , M. Bellazzini , F. R. Ferraro , B. Lanzoni , C. Lardo , M. Salaris , S. Cassisi

Detailed chemical abundances of two stars in the intermediate-age Large Magellanic Cloud (LMC) globular cluster NGC~1718 are presented, based on high resolution spectroscopic observations with the MIKE spectrograph. The detailed abundances…

Astrophysics of Galaxies · Physics 2017-02-12 Charli Sakari , Andrew McWilliam , George Wallerstein

Photometric investigations have revealed that Galactic globular clusters exhibit internal metallicity variations amongst the so-called first-population stars, until now considered to have a homogeneous initial chemical composition. This is…

Astrophysics of Galaxies · Physics 2022-12-28 C. Lardo , M. Salaris , S. Cassisi , N. Bastian , A. Mucciarelli , I. Cabrera-Ziri , E. Dalessandro

As shown in previous works, globular clusters can be used to trace the overall structure of the diffuse stellar populations in early type galaxies if the number of clusters per unit stellar mass depends on metallicity. In this paper we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Juan C. Forte , E. Irene Vega , Favio R. Faifer

Medium-resolution (R~6,500) spectra of 97 giant stars in the globular cluster 47 Tucanae (47 Tuc) have been used to derive the C and N abundance sensitive index, deltaC, and to infer abundances of several key elements, Fe, Na, Si, Ca, Zr…

Solar and Stellar Astrophysics · Physics 2012-03-05 C. C. Worley , P. L. Cottrell

The spectroscopic and photometric signals of the star-to-star abundance variations found in globular clusters seem to be correlated with global parameters like the cluster's metallicity, mass and age. Understanding this behaviour could…

We report the discovery of a unique collection of metal-poor giant-stars, that exhibit anomalously high levels of $^{28}$Si, clearly above typical Galactic levels. Our sample spans a narrow range of metallicities, peaking at $-1.07\pm…

Context. Galactic Globular Clusters (GCs) are essential tools to understand the earliest epoch of the Milky Way, since they are among the oldest objects in the Universe and can be used to trace its formation and evolution. Current studies…

Solar and Stellar Astrophysics · Physics 2017-09-06 C. Muñoz , S. Villanova , D. Geisler , I. Saviane , B. Dias , R. E. Cohen , F. Mauro

We present the homogeneous reanalysis of Mg and Al abundances from high resolution UVES/FLAMES spectra for 31 red giants in the globular cluster NGC 2808. We found a well defined Mg-Al anticorrelation reaching a regime of subsolar Mg…

Solar and Stellar Astrophysics · Physics 2015-06-23 Eugenio Carretta

We present chemical abundances for 17 elements in a sample of 11 red giant branch stars in NGC 6362 from UVES spectra. NGC 6362 is one of the least massive globulars where multiple populations have been detected, yet its detailed chemical…

Solar and Stellar Astrophysics · Physics 2017-04-12 D. Massari , A. Mucciarelli , E. Dalessandro , M. Bellazzini , S. Cassisi , G. Fiorentino , R. A. Ibata , C. Lardo , M. Salaris

The view of globular clusters (GCs) as simple systems continues to unravel, revealing complex objects hosting multiple chemical peculiarities. Using differential abundance analysis, we probe the chemistry of the Type I GC, NGC 288 and the…

Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As a further observational test of this finding, we present…

We obtained FLAMES GIRAFFE+UVES spectra for both first and second-generation red giant branch (RGB) stars in the globular cluster (GC) NGC 362 and used them to derive abundances of 21 atomic species for a sample of 92 stars. The surveyed…

Astrophysics of Galaxies · Physics 2015-06-16 E. Carretta , A. Bragaglia , R. G. Gratton , S. Lucatello , V. D'Orazi , M. Bellazzini , G. Catanzaro , F. Leone , Y. Momany , A. Sollima

The globular cluster NGC 288 was previously reported to exhibit two distinct red giant branches (RGBs) in the narrow-band Calcium (HK) and Str\"omgren b and y band passes. In order to investigate this phenomenon further, we obtained…

Solar and Stellar Astrophysics · Physics 2015-06-22 Tiffany Hsyu , Christian I. Johnson , Young-Wook Lee , R. Michael Rich

As part of our on-going project on the homogeneous chemical characterization of multiple stellar populations in globular clusters (GCs), we studied NGC 5634, associated to the Sagittarius dwarf spheroidal galaxy, using high-resolution…

We have carried out a detailed abundance analysis for 21 elements in a sample of four RGB stars in the outer halo globular cluster NGC 7492 (R{GC} 25 kpc); we find [Fe/H] = -1.82 dex inferred from FeI lines (-1.79 from FeII) using high…

Astrophysics · Physics 2009-11-10 Judith G. Cohen , Jorge Melendez

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 present a chemical abundance study of three inner old halo clusters NGC 6287, NGC 6293, and NGC 6541, finding [Fe/H] = -2.01 +/- 0.05, -1.99 +/- 0.02, and -1.76 +/- 0.02, respectively, and our metallicity measurements are in good…

Astrophysics · Physics 2009-11-07 Jae-Woo Lee , Bruce W. Carney

We report for the first time Na and O abundances from high-resolution, high S/N echelle spectra of 20 red giants in NGC 2808, taken as part of the Science Verification program of the FLAMES multi-object spectrograph at the ESO VLT. In these…

Astrophysics · Physics 2009-11-10 Eugenio Carretta , Angela Bragaglia , Carla Cacciari
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