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Related papers: Isotopic Titanium Abundances in Local M Dwarfs

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We present a chemical abundance distribution study in 14 $\alpha$, odd-Z, even-Z, light, and Fe-peak elements of approximately 3200 intermediate metallicity giant stars from the APOGEE survey. The main aim of our analysis is to explore the…

Astrophysics of Galaxies · Physics 2016-03-02 Keith Hawkins , Paula Jofre , Thomas Masseron , Gerry Gilmore

High resolution spectra of 5 candidate metal-weak thick-disc stars suggested by Beers & Sommer-Larsen (1995) are analyzed to determine their chemical abundances. The low abundance of all the objects has been confirmed with metallicity…

Astrophysics · Physics 2009-10-31 P. Bonifacio , M. Centurion , P. Molaro

Lithium abundances in a selected sample of halo stars have been revised by using the new accurate IRFM effective temperatures by Alonso, Arribas & Martinez-Roger (1996a). From 41 plateau stars (Teff > 5700 and [Fe/H] <= -1.5) we found no…

Astrophysics · Physics 2015-06-24 Piercarlo Bonifacio , Paolo Molaro

Using previous measurements and quantum chemical calculations to derive the molecular properties of the TiH molecule, we obtain new values for its ro-vibrational constants, thermochemical data, spectral line lists, line strengths, and…

We explore the metal-poor regime of the Galactic disk on the distribution of stars in the [$\alpha$/M]-$V_{\phi}$ plane, to identify the most metal-poor thin disk (MPTnD) stars belonging to the low-$\alpha$ sequence. Chemical abundances and…

Astrophysics of Galaxies · Physics 2024-12-10 Guozhen Hu , Zhengyi Shao , Erbil Gugercinoglu , Wenyuan Cui

Based on high-resolution spectra obtained with the MIKE spectrograph on the Magellan telescopes we present detailed elemental abundances for 64 red giant stars in the inner and outer Galactic disk. For the inner disk sample (4-7 kpc from…

Astrophysics of Galaxies · Physics 2012-01-11 T. Bensby , A. Alves-Brito , M. S. Oey , D. Yong , J. Meléndez

We have obtained high-resolution, high signal-to-noise spectra for 899 F and G dwarf stars in the Solar neighbourhood. The stars were selected on the basis of their kinematic properties to trace the thin and thick discs, the Hercules…

Astrophysics of Galaxies · Physics 2015-05-13 T. Bensby , S. Feltzing

We show that the Galactic thick disk reaches at least solar metallicities, and that it experienced strong chemical enrichment during a period of ~3 Gyr, ending around 8-9 Gyr ago. This finding puts further constraints on the relation and…

Astrophysics · Physics 2010-11-11 T. Bensby , A. R. Zenn , M. S. Oey , S. Feltzing

[ABRIDGED] We report the results of a high-resolution spectroscopic survey of all the stars more luminous than Mv = 6.5 mag within 14.5 pc from the Sun. We derive stellar parameters and perform a preliminary abundance and kinematic analysis…

Astrophysics · Physics 2016-08-30 Carlos Allende Prieto , Paul S. Barklem , David L. Lambert , Katia Cunha

The Milky Way ultra-faint dwarf galaxies (UFDs) contain some of the oldest, most metal-poor stars in the Universe. We present [Mg/Fe], [Si/Fe], [Ca/Fe], [Ti/Fe], and mean [alpha/Fe], abundance ratios for 61 individual red giant branch stars…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Luis C. Vargas , Marla Geha , Evan N. Kirby , Joshua D. Simon

We used the ugr magnitudes of 1,437,467 F-G type main-sequence stars with metal abundance -2<[Fe/H]<+0.2 dex and estimated radial and vertical metallicity gradients for high Galactic-latitude fields (b>50) of the Milky Way Galaxy. The…

Astrophysics of Galaxies · Physics 2019-01-16 S. Tuncel Guctekin , S. Bilir , S. Karaali , O. Plevne , S. Ak

We analyze the oxygen abundances of a stellar sample representative of the two major Galactic populations: the thin and thick disks. The aim is to investigate the differences between members of the Galactic disks and to contribute to the…

A sample of mostly old metal-rich dwarf and turn-off stars with high eccentricity and low maximum height above the Galactic plane has been identified. From their kinematics, it was suggested that the inner disk is their most probable…

Solar and Stellar Astrophysics · Physics 2011-09-29 M. Trevisan , B. Barbuy , K. Eriksson , B. Gustafsson , M. Grenon , L. Pompéia

We present Li and Fe abundances for 87 stars in the GC M4,obtained with GIRAFFE high-resolution spectra. The targets range from the TO up to the RGB Bump. The Li abundance in the TO stars is uniform, with an average value A(Li)=2.30+-0.02…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Mucciarelli , M. Salaris , L. Lovisi , F. R. Ferraro , L. Lanzoni , S. Lucatello , R. G. Gratton

A non-LTE analysis of K I resonance lines at 7664.91 and 7698.97 A was carried out for 15 red giants belonging to three globular clusters of different metallicity (M 4, M 13, and M 15) along with two reference early-K giants (rho Boo and…

Solar and Stellar Astrophysics · Physics 2015-05-13 Y. Takeda , H. Kaneko , N. Matsumoto , S. Oshino , H. Ito , T. Shibuya

We present elemental abundances of 13 microlensed dwarf and subgiant stars in the Galactic bulge, which constitute the largest sample to date. We show that these stars span the full range of metallicity from Fe/H=-0.8 to +0.4, and that they…

We provide detailed abundance analyses of 8 candidate super-metal-rich stars. Five of them are confirmed to have [Fe/H] > 0.2 dex, the generally-accepted limit for super-metal-richness. Furthermore, we derive abundances of several elements…

Astrophysics · Physics 2007-05-23 Sofia Feltzing , Guillermo Gonzalez

How many low-mass stars, brown dwarfs and free-floating planets are in the Milky Way? And how are they distributed in our Galaxy? Recent studies of Milky Way interlopers in high-redshift observations have revealed a 150-300 pc thick disk of…

Astrophysics of Galaxies · Physics 2023-06-27 Benne Holwerda , Nor Pirzkal , Adam Burgasser , Chih-Chun Hsu

We present the results of determination of the barium abundance considering the non-LTE (NLTE) effects in 172 dwarf stars in the metallicity range of -1< [Fe/H] <+0.3, assigned to different Galactic substructures by kinematic criteria. We…

Solar and Stellar Astrophysics · Physics 2015-05-27 S. Korotin , T. Mishenina , T. Gorbaneva , C. Soubiran

Of all the light elements, lithium is the most sensitive indicator of stellar evolution. This review discusses current data on the abundance of lithium in the atmospheres of A-, F-, G-, and K-stars of different types, as well as the…

Solar and Stellar Astrophysics · Physics 2017-01-23 L. S. Lyubimkov
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