English
Related papers

Related papers: Principal Component Analysis on Chemical Abundance…

200 papers

To understand the formation and evolution of the different stellar populations within our Galaxy it is essential to combine detailed kinematical and chemical information for large samples of stars. We derive chemical abundances of Cu, Zn,…

Solar and Stellar Astrophysics · Physics 2017-10-25 E. Delgado Mena , M. Tsantaki , V. Zh. Adibekyan , S. G. Sousa , N. C. Santos , J. I. González Hernández , G. Israelian

At present none of Galactic chemical evolution (GCE) models provides a self-consistent description of observed trends for all iron-peak elements with metallicity simultaneously. The question is whether the discrepancy is due to deficiencies…

Solar and Stellar Astrophysics · Physics 2015-05-14 Maria Bergemann , Thomas Gehren

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

Using the DR12 public release of APOGEE data, we show that thin and thick disk separate very well in the space defined by [$\alpha$/Fe], [Fe/H] and [C/N]. Thick disk giants have both higher [C/N] and higher [$\alpha$/Fe] than do thin disk…

Solar and Stellar Astrophysics · Physics 2015-09-03 T. Masseron , G. Gilmore

Many works have found unusual characteristics of elemental abundances in nearby dwarf galaxies. This implies that there is a key factor of galactic evolution that is different from that of the Milky Way (MW). The chemical abundances of the…

Astrophysics of Galaxies · Physics 2013-09-09 Hongjie Li , Wenyuan Cui , Bo Zhang

In this study we investigate the chemical enrichment of the rapid neutron-capture process in the Small Magellanic Cloud (SMC). We measure [Eu/Fe] abundance ratios in 209 giant stars that are confirmed members of the SMC, providing the first…

Astrophysics of Galaxies · Physics 2025-11-13 Samuele Anoardo , Alessio Mucciarelli , Marco Palla , Lorenzo Santarelli , Carmela Lardo , Donatella Romano

The chemical evolution of neutron capture elements in the Milky Way disc is still a matter of debate. We aim to understand the chemical evolution of r-process elements in Milky Way disc. We focus on three pure r-process elements Eu, Gd, and…

Astrophysics of Galaxies · Physics 2018-11-28 G. Guiglion , P. de Laverny , A. Recio-Blanco , N. Prantzos

Using data from the GALAH survey, we explore the dependence of elemental abundances on stellar age and metallicity among Galactic disc stars. We find that the abundance of most elements can be predicted from age and [Fe/H] with an intrinsic…

Many nucleosynthetic channels create the elements, but two-parameter models characterized by $\alpha$ and Fe nonetheless predict stellar abundances in the Galactic disk to accuracies of 0.02 to 0.05 dex for most measured elements, near the…

Using results of nucleosynthesis calculations for theoretical core-collapse supernova models with various progenitor's masses, it is shown that abundance patterns of C, Mg, Si, Ca, and H seen in extremely metal-deficient stars with [Fe/H] <…

Astrophysics · Physics 2009-10-30 Toshikazu Shigeyama , Takuji Tsujimoto

We have analyzed high-resolution and high signal-to-noise ratio optical spectra of nearby FGK stars with and without detected giant planets in order to homogeneously measure their photospheric parameters, mass, age, and the abundances of…

Solar and Stellar Astrophysics · Physics 2015-07-29 R. da Silva , A. C. Milone , H. J. Rocha-Pinto

The abundance scatter of heavier r-process elements (Z > 56) relative to Fe ([r/Fe]) in metal-poor stars preserves excellent information of the star formation history and provides important insights into the various situations of the…

Solar and Stellar Astrophysics · Physics 2018-05-11 Guochao Yang , Hongjie Li , Nian Liu , Lu Zhang , Wenyuan Cui , Yanchun Liang , Ping Niu , Bo Zhang

[ABRIDGED]We study the carbon abundances with a twofold objective. On the one hand, we want to evaluate the behaviour of carbon in the context of Galactic chemical evolution. On the other hand, we focus on the possible dependence of carbon…

Solar and Stellar Astrophysics · Physics 2021-12-01 E. Delgado Mena , V. Adibekyan , N. C. Santos , M. Tsantaki , J. I. González Hernández , S. G. Sousa , S. Bertrán de Lis

We show that the low ratios of $\alpha$ elements (Mg, Si, and Ca) to Fe recently found for a small fraction of extremely metal-poor stars can be naturally explained with the nucleosynthesis yields of core-collapse supernovae, i.e.,…

Astrophysics of Galaxies · Physics 2015-06-19 Chiaki Kobayashi , Miho N. Ishigaki , Nozomu Tominaga , Ken'ichi Nomoto

Studies of nucleosynthesis in neutrino-driven winds from nascent neutron stars show that the elements from Sr through Ag with mass numbers A~88-110 are produced by charged-particle reactions (CPR) during the alpha-process in the winds.…

Astrophysics · Physics 2009-11-13 Y. -Z. Qian , G. J. Wasserburg

We present detailed chemical abundances in 8 clusters in the Large Magellanic Cloud (LMC). We measure abundances of 22 elements for clusters spanning a range in age of 0.05 to 12 Gyr, providing a comprehensive picture of the chemical…

Astrophysics of Galaxies · Physics 2015-06-03 J. E. Colucci , R. A. Bernstein , S. A. Cameron , A. McWilliam

We report detailed chemical abundance analysis of 27 RGB stars towards the Galactic bulge in Baade's Window for elements produced by massive stars: O, Na, Mg, Al, Si, Ca and Ti. All of these elements are overabundant in the bulge relative…

Astrophysics · Physics 2011-02-11 Jon. P. Fulbright , Andrew McWilliam , R. Michael Rich

Studies of elemental abundances in stars belonging to the thin and the thick disk of our Galaxy are reviewed. Edvardsson et al. (1993) found strong evidence of [alpha/Fe] variations among F and G main sequence stars with the same [Fe/H] and…

Astrophysics · Physics 2007-05-23 Poul E. Nissen

We present a uniform study of the chemical abundances of 12 elements (Si, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Na, Mg, and Al) derived from the spectra of 451 stars observed as part of one of the HARPS GTO planet search programs. Sixty eight of…

Astrophysics of Galaxies · Physics 2009-11-13 V. Neves , N. C. Santos , S. G. Sousa , A. C. M. Correia , G. Israelian

For the first time we show the detailed late-stage chemical evolution history of small nearby dwarf spheroidal galaxy in the Local Group. We present the results of a high resolution (R$\sim$20000) FLAMES/GIRAFFE abundance study at ESO/VLT…