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Related papers: Individual Alpha Elements, C, N, and Ba in Early T…

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It is now clear that abundance variations from star-to-star among the light elements, particularly C, N, O, Na and Al, are ubiquitous within galactic globular clusters; they appear seen whenever data of high quality is obtained for a…

Astrophysics · Physics 2007-05-23 Judith G. Cohen

High resolution, high S/N spectra have been obtained for a sample of 90 F and G main-sequence disk stars covering the metallicity range -1.0 < [Fe/H] < +0.1, and have been analysed in a parallel way to the work of Edvardsson et al. (1993).…

Astrophysics · Physics 2009-10-31 Y. Q. Chen , P. E. Nissen , G. Zhao , H. W. Zhang , T. Benoni

We present a comprehensive abundance analysis of 27 heavy elements in bright giant stars of the globular clusters M4 and M5 based on high resolution, high signal-to-noise ratio spectra obtained with the Magellan Clay Telescope. We confirm…

We present the analysis of an extensive set of new and literature high quality data concerning Fe, C, N, O, Na, and Mg, exploiting the Teff scale determined in Gratton et al. (1996), and the non-LTE abundance corrections computed in Gratton…

Astrophysics · Physics 2007-05-23 Eugenio Carretta , Raffaele Gratton , Chris Sneden

Low-metallicity stars preserve the signatures of the first stellar nucleosynthesis events in the Galaxy, as their surface abundances reflect the composition of the interstellar medium from which they were born. Aside from primordial Big…

Solar and Stellar Astrophysics · Physics 2025-03-25 Khalil Farouqi , Anna Frebel , Friedrich-Karl Thielemann

In an attempt of clarifying the connection between the photospheric abundance anomalies and the stellar rotation as well as of exploring the nature of "normal A" stars, the abundances of seven elements (C, O, Si, Ca, Ti, Fe, and Ba) and the…

Astrophysics · Physics 2017-01-18 Yoichi Takeda , Inwoo Han , Dong-Il Kang , Byeong-Cheol Lee , Kang-Min Kim

We confirm the difference of chemical abundance between stars with and without exoplanet, as well as present the relation between chemical abundances and the physical properties of exoplanets such as planetary mass and semi-major axis of…

Solar and Stellar Astrophysics · Physics 2011-09-02 Wonseok Kang , Sang-Gak Lee , Kang-Min Kim

The detailed abundance patterns of the stars within galaxies provide a unique window into the history of star formation (SF) at early times. Two widely used `chronometers' include the alpha and iron-peak elements, which are created on short…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Charlie Conroy , Pieter van Dokkum , Genevieve J. Graves

We determine relative abundance ratios for the neutron-capture elements Zr, La, Ce, Nd, and Eu for a sample of 27 Galactic dwarf stars with -1.5 < [Fe/H] <-0.8. We also measure the iron-peak element Sc. These stars separate into three…

Solar and Stellar Astrophysics · Physics 2017-01-18 C. K. Fishlock , D. Yong , A. I. Karakas , A. Alves-Brito , J. Melendez , P. E. Nissen , C. Kobayashi , A. R. Casey

We present detailed abundance results for 9 Galactic bulge stars in Baade's Window, based on HIRES (R=45,000--60,000) spectra taken with the Keck I telescope. The alpha elements show non-uniform enhancements relative to the Solar…

Astrophysics · Physics 2007-05-23 Andrew McWilliam , R. Michael Rich

HARPS-N spectra with S/N > 250 and MARCS model atmospheres were used to derive abundances of C, O, Na, Mg, Al, Si, Ca, Ti, Cr, Fe, Ni, Zn, and Y in ten stars from the Kepler LEGACY sample (including the binary pair 16 Cyg A and B) selected…

Solar and Stellar Astrophysics · Physics 2017-12-13 P. E. Nissen , V. Silva Aguirre , J. Christensen-Dalsgaard , R. Collet , F. Grundahl , D. Slumstrup

We have observed high-dispersion echelle spectra of main-sequence stars in five nearby young associations -- Argus, Carina-Near, Hercules-Lyra, Orion and Subgroup B4 -- and derived abundances for elements ranging from Na to Eu. These are…

Solar and Stellar Astrophysics · Physics 2015-10-21 Arumalla B. S. Reddy , David L. Lambert

We present a detailed elemental abundance study of 90 F and G dwarf, turn-off and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11…

Elemental abundance patterns can provide vital clues to the formation and enrichment history of a stellar population. Here we present an investigation of the Galactic bulge, where we apply principal component abundance analysis (PCAA)---a…

Astrophysics of Galaxies · Physics 2012-08-31 Brett H. Andrews , David H. Weinberg , Jennifer A. Johnson , Thomas Bensby , Sofia Feltzing

We examine the origin of heavy elements in the intracluster medium (ICM) of galaxy clusters, concentrating upon the roles played by supernovae (SNe) Types Ia and II. The most accurately determined elemental abundances, Si and Fe, imply a…

Astrophysics · Physics 2007-05-23 Brad K. Gibson , Emma J. Woolaston

We present detailed abundance measurements for 45 globular clusters (GCs) in galaxies in (and, in one case, beyond) the Local Group. The measurements are based on new high-resolution integrated-light spectra of GCs in NGC 185, NGC 205, M31,…

Astrophysics of Galaxies · Physics 2022-04-20 S. S. Larsen , P. Eitner , E. Magg , M. Bergemann , C. A. S. Moltzer , J. P. Brodie , A. J. Romanowsky , J. Strader

We use our new stellar population models, which include effects from variable element abundance ratios, to model the Ca4227 absorption line indices of early-type galaxies (Trager et al.), and to derive calcium element abundances. We find…

Astrophysics · Physics 2009-11-07 Daniel Thomas , Claudia Maraston , Ralf Bender

NGC 6558 is a bulge globular cluster with a blue horizontal branch (BHB), combined with a metallicity of [Fe/H]~-1.0. It is similar to HP 1 and NGC 6522, which could be among the oldest objects in the Galaxy. Element abundances in these…

Solar and Stellar Astrophysics · Physics 2018-11-28 B. Barbuy , L. Muniz , S. Ortolani , H. Ernandes , B. Dias , I. Saviane , L. Kerber , E. Bica , A. Pérez-Villegas , L. Rossi , E. V. Held

Theories of thick disk formation can be differentiated by measurements of stellar elemental abundances. We have undertaken a study of metal-poor stars selected from the RAVE spectroscopic survey of bright stars to establish whether or not…

We present the first in a series of papers studying the X-ray properties of 28 early type galaxies spanning ~3 orders of magnitude in L_x. We report emission-weighted constraints for Fe, O, Ne, Mg, Si, S and Ni. We find no evidence of the…

Astrophysics · Physics 2009-11-10 Philip J. Humphrey , David A. Buote
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