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Related papers: Complexity on Small Scales III: Iron and alpha Ele…

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We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l,b)=(+5.25,-3.02) and (0,-12). The (+5.25,-3.02)…

Solar and Stellar Astrophysics · Physics 2015-06-22 Christian I. Johnson , R. Michael Rich , Chiaki Kobayashi , Andrea Kunder , Andreas Koch

Chlorine abundances are reported in 15 evolved giants and one M dwarf in the solar neighborhood. The Cl abundance was measured using the vibration-rotation 1-0 P8 line of H$^{35}$Cl at 3.69851 $\mu$m. The high resolution L-band spectra were…

Solar and Stellar Astrophysics · Physics 2016-12-05 Z. G. Maas , C. A. Pilachowski , K. Hinkle

We performed an uniform spectroscopic analysis of 1111 FGK dwarfs observed as part of the HARPS GTO planet search program. We applied a purely chemical approach, based on [alpha/Fe] ratio, to distinguish the various stellar components in…

Earth and Planetary Astrophysics · Physics 2013-07-09 V. Zh. Adibekyan , N. C. Santos , S. G. Sousa , G. Israelian , P. Figueira

We measured [Fe/H] and [$\alpha$/Fe] using spectral synthesis of low-resolution stellar spectroscopy for 70 individual red giant branch stars across four fields spanning the outer disk, Giant Stellar Stream (GSS), and inner halo of M31.…

We present a detailed analysis of 26 barium stars, including dwarf barium stars, providing their atmospheric parameters (Teff, log g, [Fe/H], vt) and elemental abundances. We aim at deriving gravities and luminosity classes of the sample…

Astrophysics · Physics 2009-11-11 Dinah M. Allen , Beatriz Barbuy

The elemental abundances of symbiotic giants are essential to address the role of chemical composition in the evolution of symbiotic binaries, to map their parent population, and to trace their mass transfer history. However, the number of…

Solar and Stellar Astrophysics · Physics 2015-11-16 Cezary Galan , Joanna Mikolajewska , Kenneth H. Hinkle , Richard R. Joyce

We present the first fluorine measurements in 12 normal giants belonging to the Galactic thin and thick disks using spectra obtained with the Phoenix infrared spectrometer on the 2.1m telescope at Kitt Peak. Abundances are determined from…

Astrophysics of Galaxies · Physics 2024-06-06 K. E. Brady , C. A. Pilachowski , V. Grisoni , Z. G. Maas , K. A. Nault

In this paper we present an homogeneous analysis of photospheric abundances based on high-resolution spectroscopy of a sample of 182 barium stars and candidates. We determined atmospheric parameters, spectroscopic distances, stellar masses,…

Solar and Stellar Astrophysics · Physics 2016-04-27 D. B. de Castro , C. B. Pereira , F. Roig , E. Jilinski , N. A. Drake , C. Chavero , J. V. Sales Silva

Chemical enrichment signatures strongly constrain galaxy formation and evolution, and a detailed understanding of abundance patterns provides clues regarding the nucleosynthetic production pathways of elements. Using the SDSS-IV MaNGA IFU…

We describe and employ a stacking procedure to investigate abundances derived from the low S/N spectra obtained in the Carnegie RR Lyrae Survey (CARRS; Kollmeier et al. 2013). We find iron metallicities that extend from [Fe/H] ~ -2.5 to…

We present measurements of [Fe/H] for six M supergiant stars and three giant stars within 0.5 pc of the Galactic Center (GC) and one M supergiant star within 30 pc of the GC. The results are based on high-resolution (lambda / Delta lambda…

We have derived new detailed abundances of Mg, Ca, and the Fe-group elements Sc through Zn (Z = 21-30) for 37 main sequence turnoff very metal-poor stars ([Fe/H] <= -2.1). We analyzed Keck HIRES optical and near-UV high signal-to-noise…

We present [Fe/H] and [$\alpha$/Fe] abundances, derived using spectral synthesis techniques, for stars in M31's outer stellar halo. The 21 [Fe/H] measurements and 7 [$\alpha$/Fe] measurements are drawn from fields ranging from 43 to 165 kpc…

We present radial velocities and chemical abundance ratios of [Fe/H], [O/Fe], [Si/Fe], and [Ca/Fe] for 264 red giant branch (RGB) stars in three Galactic bulge off-axis fields located near (l,b)=(-5.5,-7), (-4,-9), and (+8.5,+9). The…

We explored the occurrence rate of small close-in planets among $\textit{Kepler}$ target stars as a function of the iron abundance and the stellar total velocity $V_\mathrm{tot}$. We estimated the occurrence rate of those planets by…

Earth and Planetary Astrophysics · Physics 2019-07-18 Dolev Bashi , Shay Zucker

Previous work on the abundances of C, O, Na, Mg, Si, Ca, Ti, Cr, Mn, Fe, Ni, Cu, and Zn in low-alpha (accreted) and high-alpha (in situ born) halo stars is extended to include the abundances of Sc, V, and Co, enabling us to study the…

Astrophysics of Galaxies · Physics 2023-12-14 P. E. Nissen , A. M. Amarsi , Á. Skúladóttir , W. J. Schuster

Using high-resolution spectroscopy, we provide a determination of [Fe/H] and [Ca/H] for confirmed red-giant branch member stars of the Hercules dwarf spheroidal galaxy. Based on this we explore the ages of the prevailing stellar populations…

Astrophysics of Galaxies · Physics 2015-05-20 D. Adén , K. Eriksson , S. Feltzing , E. K. Grebel , A. Koch , M. I. Wilkinson

We summarize a selection process to identify red giants in the direction of the southern warp of the Galactic disk, employing VI_C photometry and multi-object spectroscopy. We also present results from follow-up high-resolution, high-S/N…

Astrophysics · Physics 2008-11-26 Bruce W. Carney , David Yong , Luisa de Almeida , Patrick Seitzer

The present study of spectra of twelve metal-rich cool dwarf stars, carefully selected in order to cover a range of temperatures (~4400 - 6000 K), is a follow up on Feltzing & Gustafsson (1998, A&AS 129, 237) with the aim to understand the…

Astrophysics · Physics 2007-05-23 P. Thoren , S. Feltzing

Studies of the early chemical evolution of some larger dwarf galaxies ( $>10^7$ solar masses) are limited by the small number of stars known at low metallicities in these systems. Here we present metallicities and carbon abundances for…

Astrophysics of Galaxies · Physics 2020-10-14 Anirudh Chiti , Kylie Y. Hansen , Anna Frebel