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Related papers: Abundance analysis of the outer halo globular clus…

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Globular clusters (GCs) in the outer Milky Way halo are important tracers of the assembly history of our Galaxy. Only a few of these objects show spreads in heavier elements beyond the canonical light-element variations that have…

Astrophysics of Galaxies · Physics 2019-07-05 Andreas Koch , Siyi Xu , R. Michael Rich

At a Galactocentric distance of 27 kpc, Pal 13 is an old globular cluster (GC) in the outer halo. We present a chemical abundance analysis of this remote system from high-resolution spectra obtained with Keck/HIRES. Owing to the low…

Astrophysics of Galaxies · Physics 2019-11-27 Andreas Koch , Patrick Côté

Context: Chemical element abundances for distant Galactic globular clusters (GCs) hold important clues to the origin of the Milky Way halo and its substructures. Aims: We study the chemical composition of red giant stars in Pal 4 - one of…

Astrophysics of Galaxies · Physics 2015-05-18 Andreas Koch , Patrick Côté

Context: Globular clusters (GCs) in the outer halo are important probes of the composition and origin of the Galactic stellar halo. Aims: We derive chemical element abundance ratios in red giants belonging to the remote (R~90 kpc) GC Pal 3…

Astrophysics of Galaxies · Physics 2015-05-13 Andreas Koch , Patrick Côté , Andrew McWilliam

Detailed chemical abundances for twenty one elements are presented for four red giants in the anomalous outer halo globular cluster Palomar 1 ($R_{\rm{GC}} = 17.2$ kpc, $Z=3.6$ kpc) using high-resolution (R=36000) spectra from the High…

Astrophysics of Galaxies · Physics 2015-05-28 Charli M. Sakari , Kim A. Venn , Mike Irwin , Wako Aoki , Nobuo Arimoto , Aaron Dotter

We present a chemical abundance analysis of the tidally disrupted globular cluster (GC) Palomar 5. By co-adding high-resolution spectra of 15 member stars from the cluster's main body, taken at low signal-to-noise with the Keck/HIRES…

Astrophysics of Galaxies · Physics 2017-05-24 Andreas Koch , Patrick Côté

We present the first comprehensive abundance study of the massive, outer halo globular cluster (GC) M 75 (NGC 6864). This unique system shows a very extended trimodal horizontal branch (HB), but no other clues for multiple populations have…

Astrophysics of Galaxies · Physics 2013-01-11 Nikolay Kacharov , Andreas Koch

The differences between the neutron-capture element abundances of halo stars are important to our understanding of the nucleosynthesis of elements heavier than the iron group. We present a detailed abundance analysis of carbon and twelve…

Solar and Stellar Astrophysics · Physics 2012-03-27 S. Liu , P. E. Nissen , W. J. Schuster , G. Zhao , Y. Q. Chen , Y. C. Liang

We present a detailed abundance analysis for 21 elements based on high dispersion, high spectral resolution Keck spectra for four members of the outer halo ``young'' Galactic globular cluster Pal 12. All four stars show identical abundance…

Astrophysics · Physics 2015-06-24 Judith Cohen

Globular clusters (GCs) are the oldest stellar systems in the Milky Way. Long time considered as simple stellar populations, nowadays we recognize their complex star formation history through precise abundance analysis of a variety of…

Astrophysics of Galaxies · Physics 2015-06-05 Nikolay Kacharov , Andreas Koch

The FLAMES survey ``Na-O anti-correlation and HB" uncovered the modern standard for globular clusters (GCs), that is their ubiquitous multiple stellar populations (MPs) distinct by the abundance of proton-capture elements. That survey can…

Solar and Stellar Astrophysics · Physics 2026-03-25 Eugenio Carretta

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: 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

High resolution (R > 40 000) and high S/N spectra have been acquired with UVES on the VLT-Kueyen (Paranal Observatory, ESO Chile) for several main sequence turnoff stars (V ~ 17 mag) and subgiants at the base of the Red Giant Branch (V ~ 16…

Astrophysics · Physics 2007-05-23 G. James , P. Francois , P. Bonifacio , E. Carretta , R. G. Gratton , F. Spite

Globular clusters (GCs) are key to understanding the formation and evolution of our Galaxy. While the abundances of light and Fe-peak elements in GCs have been widely studied, investigations into heavier, neutron-capture elements -- and…

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

The globular cluster HP~1 is projected at only 3.33 degrees from the Galactic center. Together with its distance, this makes it one of the most central globular clusters in the Milky Way. It has a blue horizontal branch (BHB) and a…

Solar and Stellar Astrophysics · Physics 2016-06-22 B. Barbuy , E. Cantelli , A. Vemado , H. Ernandes , S. Ortolani , I. Saviane , E. Bica , D. Minniti , B. Dias , Y. Momany , V. Hill , M. Zoccali , C. Siqueira-Mello

47 Tuc is an ideal target to study chemical evolution and GC formation in massive more metal-rich GCs since is the closest, massive GC. We present chemical abundances for O, Na, Al, Si, Ca, Ti, Fe, Ni, La, and Eu in 164 red giant branch…

We present the results of the analysis of high-resolution spectra obtained with UVES-FLAMES@VLT for six red giant branch stars in the outer-halo metal-poor ([Fe/H]I=-1.98 and [Fe/H]II=-1.83) Galactic globular cluster NGC 5694, which has…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Mucciarelli , M. Bellazzini , M. Catelan , E. Dalessandro , P. Amigo , M. Correnti , C. Cortés , V. D'Orazi

We report for the first time on the chemical composition of the halo cluster NGC 5897 (R=12.5 kpc), based on chemical abundance ratios for 27 alpha-, iron-peak, and neutron-capture elements in seven red giants. From our high-resolution,…

Astrophysics of Galaxies · Physics 2014-05-08 Andreas Koch , Andrew McWilliam
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