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Related papers: Magnesium isotope ratios in Hyades stars

200 papers

Using standard 1D-LTE model atmosphere analysis, we provide an in-depth investigation of iron abundance as derived from neutral and singly ionization iron lines (Fe {\scriptsize{I, II}}) in nearby star clusters. Specifically, we replicate…

Solar and Stellar Astrophysics · Physics 2017-09-06 Patrick D. Aleo , Alexander C. Sobotka , Ivan Ramirez

From high resolution spectra of 61 cool dwarfs and giants, Mg isotopic abundance ratios 24Mg:25Mg:26Mg are derived from spectral synthesis of the MgH A-X lines near 5140A. Our sample spans the range -2.5 < [Fe/H] < 0.1, including the first…

Astrophysics · Physics 2009-11-10 David Yong , David L. Lambert , Inese I. Ivans

It has been occasionally suggested that Fe abundances of K dwarfs derived from Fe I and Fe II lines show considerable discrepancies and oxygen abundances determined from high-excitation O I 7771-5 triplet lines are appreciably overestimated…

Solar and Stellar Astrophysics · Physics 2020-04-08 Yoichi Takeda , Satoshi Honda

We have measured phosphorus abundances in nine disk stars between -1 $<$ [Fe/H] $<$ -0.5 and in 12 members of the Hyades open cluster using two P I lines at 1.06 $\mu$m. High resolution infrared spectra were obtained using Phoenix on Gemini…

Solar and Stellar Astrophysics · Physics 2019-11-07 Z. G. Maas , G. Cescutti , C. A. Pilachowski

We present a differential abundance analysis of Hyades F-K dwarfs in search for evidence of stellar enrichment from accreted hydrogen deficient disk material. Metallicites and relative abundance ratios of several species have been…

Astrophysics · Physics 2008-11-26 Diane B. Paulson , Christopher Sneden , William D. Cochran

We report the first survey of chemical abundances in M and K dwarf stars using atomic absorption lines in high resolution spectra. We have measured Fe and Ti abundances in 35 M and K dwarf stars using equivalent widths measured from (lambda…

Astrophysics · Physics 2009-11-10 Vincent M. Woolf , George Wallerstein

In an attempt to carry out a systematic study on the behavior of the photospheric abundances of Li, C, and O (along with Fe) for Hyades main-sequence stars in the T_eff range of ~5000-7000K, we conducted an extensive spectrum-synthesis…

Solar and Stellar Astrophysics · Physics 2015-06-12 Yoichi Takeda , Satoshi Honda , Takashi Ohnishi , Michiko Ohkubo , Ryuko Hirata , Kozo Sadakane

We present atmospheric parameters for 51 nearby FG dwarfs uniformly distributed over the -2.60 < [Fe/H] < +0.20 metallicity range that is suitable for the Galactic chemical evolution research. Lines of iron, Fe I and Fe II, were used to…

Solar and Stellar Astrophysics · Physics 2015-08-06 T. Sitnova , G. Zhao , L. Mashonkina , Y. Q. Chen , F. Liu , Yu. Pakhomov , K. Tan , M. Bolte , S. Alexeeva , F. Grupp , J. -R. Shi , H. -W. Zhang

We present equivalent widths, improved model atmosphere parameters, and revised abundances for 14 species of 11 elements derived from high resolution optical spectroscopy of 311 metal-poor stars. All of these stars had their parameters…

Solar and Stellar Astrophysics · Physics 2025-02-27 Sanil Mittal , Ian U. Roederer

Isotopic abundance ratios 24^Mg:25^Mg:26^Mg are derived for 20 stars from high- resolution spectra of the MgH A-X 0-0 band at 5140AA. With the exception of the weak g-band giant HR 1299, the stars are dwarfs that sample the metallicity…

Astrophysics · Physics 2009-10-31 Pamela Gay , David L. Lambert

We determine Mg abundances in 6 Gaia benchmark stars using theoretical one-dimensional (1D) hydrostatic model atmospheres, as well as temporally- and spatially-averaged 3D model atmospheres (<3D>). The stars cover a range of Teff from 4700…

Solar and Stellar Astrophysics · Physics 2017-09-27 Maria Bergemann , Remo Collet , Anish M. Amarsi , Mikhail Kovalev , Gregory Ruchti , Zazralt Magic

We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…

Astrophysics · Physics 2016-08-30 Carlos Abia , Lyudmila Mashonkina

We present results of a detailed chemical analysis performed on 23 main-sequence turnoff stars having -3.4<=[Fe/H]<=-2.2, a sample selected to be highly homogeneous in T_eff and log(g). We investigate the efficiency of mixing in the early…

Astrophysics · Physics 2009-11-10 E. Arnone , S. G. Ryan , D. Argast , J. E. Norris , T. C. Beers

One of the most important factors in determining the stellar lithium abundance is the effective temperature. In a previous study by the authors, new effective temperatures Teff for sixteen metal-poor halo dwarfs were derived using a local…

Solar and Stellar Astrophysics · Physics 2015-05-18 A. Hosford , A. E. Garcia Perez , R. Collet , S. G. Ryan , J. E. Norris , K. A. Olive

Spectroscopic determinations of Rubidium abundances were conducted by applying the spectrum fitting method to the Rb I 7800 line for an extensive sample of ~500 late-type dwarfs as well as giants (including Hyades cluster stars) belonging…

Solar and Stellar Astrophysics · Physics 2021-04-28 Yoichi Takeda

Neutral Fe lines in metal-poor stars yield conflicting abundances depending on whether and how deviations from local thermodynamic equilibrium (LTE) are considered. We have collected new high resolution and high signal-to-noise ultraviolet…

Solar and Stellar Astrophysics · Physics 2018-07-04 Ian U. Roederer , Christopher Sneden , James E. Lawler , Jennifer S. Sobeck , John J. Cowan , Ann Merchant Boesgaard

In several instances chemical abundances of dwarf and giant stars are used simultaneously under the assumption that they share the same abundance scale. This assumption might have implications in different astrophysical contexts. We aim to…

Solar and Stellar Astrophysics · Physics 2015-12-23 Letícia Dutra-Ferreira , Luca Pasquini , Rodolfo Smiljanic , Gustavo F. Porto de Mello , Matthias Steffen

The atmospheric parameters and iron abundance of the Sloan Digital Sky Survey (SDSS) spectrophotometric standard star BD +17 4708 are critically examined using up-to-date Kurucz model atmospheres, LTE line formation calculations, and…

Astrophysics · Physics 2009-11-11 I. Ramirez , C. Allende Prieto , S. Redfield , D. L. Lambert

The homogeneous data sets for the calcium and scandium abundances accounting for departures from LTE were obtained for a sample of 54 metallic-line (Am) stars. The Ca and Sc abundances were found to correlate with effective temperature…

Solar and Stellar Astrophysics · Physics 2024-07-29 L. I. Mashonkina , Yu. A. Fadeyev

We have derived Fe abundances of 16 solar-type Pleiades dwarfs by means of an equivalent width analysis of Fe I and Fe II lines in high-resolution spectra obtained with the Hobby - Eberly Telescope and High Resolution Spectrograph.…

Solar and Stellar Astrophysics · Physics 2015-05-19 S. C. Schuler , A. L. Plunkett , J. R. King , M. H. Pinsonneault
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