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We have performed a new abundance analysis of Carina Red Giant (RG) stars from spectroscopic data collected with UVES (high resolution) and FLAMES/GIRAFFE (high and medium resolution) at ESO/VLT. The former sample includes 44 RGs, while the…

We have compiled a sample of 699 stars from the recent literature with detailed chemical abundance information (spanning -4.2 < [Fe/H] < +0.3), and we compute their space velocities and Galactic orbital parameters. We identify members of…

Astrophysics · Physics 2009-11-13 Ian U. Roederer

New space missions, such as NASA TESS or ESA PLATO, will focus on bright stars, which have been largely ignored by modern large surveys, especially in the northern sky. Spectroscopic information is of paramount importance in characterising…

Precise abundance ratios are determined for 94 dwarf stars with 5200 < Teff < 6300 K, -1.6 < [Fe/H] < -0.4, and distances D < 335 pc. Most of them have halo kinematics, but 16 thick-disk stars are included. Equivalent widths of atomic lines…

Astrophysics of Galaxies · Physics 2015-05-18 Poul E. Nissen , William J. Schuster

The chemical composition of stars in open clusters provides the best information on the chemical evolution of stars via comparison of the main sequence stars with the evolved giants. This is a case study of the abundances in the dwarfs and…

Solar and Stellar Astrophysics · Physics 2019-06-26 Michael G. Lum , Ann Merchant Boesgaard

We derive abundances of Fe, Na, O, and s-elements from GIRAFFE@VLT spectra for more than 200 red giant stars in the Milky Way satellite Omega Centauri. Our preliminary results are that: (i) we confirm that Omega Centauri exibiths large…

Solar and Stellar Astrophysics · Physics 2015-05-14 A. F. Marino , G. Piotto , R. Gratton , A. P. Milone , M. Zoccali , L. R. Bedin , S. Villanova , A. Bellini

The main atmospheric parameters and abundances of the iron group elements (vanadium, chromium, iron, cobalt and nickel) are determined for 62 red giant "clump" stars revealed in the Galactic field by the Hipparcos orbiting observatory. The…

Solar and Stellar Astrophysics · Physics 2015-05-19 E. Puzeras , G. Tautvaisiene , J. G. Cohen , D. F. Gray , S. J. Adelman , I. Ilyin , Y. Chorniy

In this paper, we present a study of the abundances of Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni in a large set of stars known to harbor giant planets, as well as in a comparison sample of stars not known to have any planet ary-mass companions.…

Astrophysics · Physics 2009-11-07 A. Bodaghee , N. C. Santos , G. Israelian , M. Mayor

Spectral data on early type galaxies is analyzed for chemical abundance with an emphasis on obtaining detailed abundances for the elements O and Si in addition to C, N, Na, Mg, Ca, Fe, and Ba. The abundance trends with velocity dispersion…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Guy Worthey , Baitian Tang , Jedidiah Serven

With an aim to study whether the close correlation between [Na/H] and [Fe/H] recently found in A-type stars further persists in the regime of B-type stars, the abundances of Na were determined for 30 selected sharp-lined late B-type stars…

Solar and Stellar Astrophysics · Physics 2015-06-17 Yoichi Takeda , Satoshi Kawanomoto , Naoko Ohishi

[Abbreviated] Context. Given their high luminosities (L>~10^4Lsun), red supergiants (RSGs) are good tracers of the chemical abundances of the young stellar population in the Milky Way and nearby galaxies. However, previous abundance…

Lithium-rich red giants have been a long-standing mystery in stellar astrophysics. A leading theory to explain these chemically peculiar and rare objects is interactions with a close companion. To investigate their companion fraction, we…

I present a review of chemical evolution models of the solar neighborhood. I give special attention to the necessary ingredients to reproduce the observed [Xi/Fe] ratios in nearby metal and super metal rich stars, and to the chemical…

Astrophysics · Physics 2007-05-23 L. Carigi

We have analyzed high-dispersion echelle spectra ($R \ga 50,000$) of red giant members for four open clusters to derive abundances for many elements. The spread in temperatures and gravities being very small among the red giants nearly the…

Astrophysics of Galaxies · Physics 2015-05-30 Arumalla B. S. Reddy , Sunetra Giridhar , David L. Lambert

Random changes in pulsation period are well established in cool pulsating stars, in particular the red giant variables: Miras, semi-regulars of types A and B, and RV Tau variables. Such effects are also observed in a handful of Cepheids,…

Solar and Stellar Astrophysics · Physics 2015-05-13 David G. Turner , J. R. Percy , T. Colivas , Leonid N. Berdnikov , Mohamed Abdel-Sabour Abdel-Latif

We have studied 23 long-lived G dwarfs that belong to the thin disk and thick disk stellar populations. Abundances have been derived for 24 elements: O, Na, Mg, Al, Si, Ca, Ti, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Sr, Y, Zr, Ba, La, Ce, Nd,…

Astrophysics · Physics 2008-11-26 Mary-Margaret Brewer , Bruce W. Carney

We present our detailed spectroscopic analysis of the chemical composition of four red giant stars in the halo globular cluster NGC 6426. We obtained high-resolution spectra using the Magellan2/MIKE spectrograph, from which we derived…

Astrophysics of Galaxies · Physics 2017-03-08 M. Hanke , A. Koch , C. J. Hansen , A. McWilliam

Since several years ago, the search for multiple populations (MPs) in Galactic open clusters (OCs) has become a field of increasing interest, particularly to the light of the general knowledge that MPs are observed in relatively massive…

Astrophysics of Galaxies · Physics 2019-07-25 Andrés E. Piatti

We present carbon abundances of red giants in Milky Way globular clusters and dwarf spheroidal galaxies (dSphs). Our sample includes measurements of carbon abundances for 154 giants in the clusters NGC 2419, M68, and M15 and 398 giants in…

Detailed chemical abundance distributions for fourteen elements are derived for eight high-probability stellar members of the solar metallicity old open cluster M67 with an age of $\sim$4 Gyr. The eight stars consist of four pairs, with…