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Related papers: Lithium, Sodium, and Potassium Abundances in Sharp…

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We present a catalog of uniformly determined stellar properties and abundances for 1626 F, G, and K stars using an automated spectral synthesis modeling procedure. All stars were observed using the HIRES spectrograph at Keck Observatory.…

Solar and Stellar Astrophysics · Physics 2016-08-24 John M. Brewer , Debra A. Fischer , Jeff A. Valenti , Nikolai Piskunov

We present high resolution observations (FWHM=15 km/sec) of the Li region in 5 stars belonging to the old (14 Gyrs), metal rich ([Fe/H]=-0.7) globular cluster 47Tuc. At the ESO NTT telescope we obtained EMMI spectra for three V about 17.4…

Astrophysics · Physics 2011-05-23 Luca Pasquini , Paolo Molaro

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

We present NLTE abundances and atmospheric parameters for three metal-poor stars ([Fe/H]<-2) in Coma Berenices ultra-faint dwarf galaxy (UFD). The derived results are based on new photometric observations obtained with the 2.5-m telescope…

Solar and Stellar Astrophysics · Physics 2018-12-05 Tatyana Sitnova , Lyudmila Mashonkina , Andrey Tatarnikov , Olga Voziakova , Marina Burlak , Yuriy Pakhomov

A comprehensive model atom for Fe with more than 3000 energy levels is presented. As a test and first application of this model atom, Fe abundances are determined for the Sun and five stars with well determined stellar parameters and…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. Mashonkina , T. Gehren , J. -R. Shi , A. J. Korn , F. Grupp

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

We have compiled a large catalogue of metallicities and abundance ratios from the literature in order to investigate abundance trends of several alpha and iron peak elements in the thin disk and the thick disk of the Galaxy. The catalogue…

Astrophysics · Physics 2009-11-10 C. Soubiran , P. Girard

In 1982, Monique and Francois Spite discovered that the 7Li abundance in the atmosphere of old metal-poor dwarf stars in the galactic halo was independent of metallicity and temperature. Since then, 7Li abundance in the Universe has become…

High Energy Astrophysical Phenomena · Physics 2014-02-24 Rachid Ouyed

While theoretical computations of the lithium abundances in Pop II stars predict variations from star to star, the most recent observations confirm the existence of a "lithium plateau" with no abundance dispersion. This apparent paradox has…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair

The light elements beryllium (Be; $Z=4$) and boron (B; $Z=5$) are mainly produced by spallation reactions between cosmic rays and carbon (C; $Z=6$), nitrogen (N; $Z=7$), and oxygen (O; $Z=8$) nuclei. Only traces of Be or B would have been…

Solar and Stellar Astrophysics · Physics 2025-10-14 Monique Spite , Beatriz Barbuy , Kefeng Tan

Un-evolved, very metal-poor stars are the most important tracers of the cosmic abundance of lithium in the early universe. Combining the standard Big Bang nucleosynthesis model with Galactic production through cosmic ray spallation, these…

Solar and Stellar Astrophysics · Physics 2015-06-16 Karin Lind , Jorge Melendez , Martin Asplund , Remo Collet , Zazralt Magic

Whether the presence of planets affects the lithium (Li) abundance of their host stars is still an open question. To investigate the difference of the Li abundance between planet-host stars (HS) and isolated stars (IS) with no detected…

With the purpose of performing a homogeneous determination of elemental abundances for members of the Lupus T association, we analyzed three chemical elements: lithium, iron, and barium. The aims were: to derive the Li abundance for ~90% of…

Solar and Stellar Astrophysics · Physics 2017-09-13 K. Biazzo , A. Frasca , J. M. Alcalá , M. Zusi , E. Covino , S. Randich , M. Esposito , C. F. Manara , S. Antoniucci , B. Nisini , E. Rigliaco , F. Getman

Several investigations of FGK stars in the solar neighborhood have suggested that thin-disk stars with an iron abundance similar to the Sun appear to show higher abundances of other elements, such as silicon, titanium, or nickel. Offsets…

Astrophysics · Physics 2007-05-23 Carlos Allende Prieto

We performed a uniform and detailed abundance analysis of 12 refractory elements (Na, Mg, Al, Si, Ca, Ti, Cr, Ni, Co, Sc, Mn, and V) for a sample of 257 G- and K-type evolved stars from the CORALIE planet search program. To date, only one…

In recent years a number of poorly studied chemical elements, such as phosphorus, sulphur, and strontium, have received special attention as important tracers of the Galactic chemical evolution. By exploiting the capabilities of the…

Solar and Stellar Astrophysics · Physics 2015-12-16 E. Caffau , S. Andrievsky , S. Korotin , L. Origlia , E. Oliva , N. Sanna , H. -G. Ludwig , P. Bonifacio

We constructed a comprehensive model atom for NeI -- NeII using the most up-to-date atomic data available and evaluated the non-local thermodynamic equilibrium (NLTE) line formation for NeI and NeII in classical 1D models representing the…

Solar and Stellar Astrophysics · Physics 2020-06-24 Sofya Alexeeva , Tianxiang Chen , Tatyana Ryabchikova , Weibin Shi , Kozo Sadakane , Masayoshi Nishimura , Gang Zhao

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

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

Context: Lithium is a fragile element, which is easily destroyed in the stellar interior. The existence of lithium-rich giants still represents a challenge for stellar evolution models. Aims: We have collected a large database of…

Solar and Stellar Astrophysics · Physics 2015-05-27 L. Monaco , S. Villanova , C. Moni Bidin , G. Carraro , D. Geisler , P. Bonifacio , O. A. Gonzalez , M. Zoccali , L. Jilkova
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