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Related papers: Pre-main sequence lithium burning. I. Weak T Tauri…

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Using high-resolution, high quality spectra we investigate the presence of $^6$Li in two lithium-poor stars that host extrasolar planetary systems. We present improved atomic and molecular line lists for the region in the vicinity of the…

Astrophysics · Physics 2009-11-10 Avi M. Mandell , Jian Ge , Norm Murray

Lithium is a fundamental element for studying the mixing mechanisms acting in the stellar interiors, for understanding the chemical evolution of the Galaxy and the Big Bang nucleosynthesis. The study of Li in stars of open clusters…

Solar and Stellar Astrophysics · Physics 2015-06-15 P. Francois , L. Pasquini , K. Biazzo , P. Bonifacio , R. Palsa

Context. As a fragile element, lithium is a sensitive probe of physical processes occurring in stellar interiors. Aims. We aim at investigating the relationship between lithium abundance and rotation rate in low-mass members of the newly…

Solar and Stellar Astrophysics · Physics 2020-04-01 J. Arancibia-Silva , J. Bouvier , A. Bayo , P. A. B. Galli , W. Brandner , H. Bouy , D. Barrado

The aims of this paper are: 1) to revisit the Tc content of a sample of oxygen-rich asymptotic giant branch (AGB) variables and 2) to increase the number of such stars for which the Li abundance has been measured to provide constraints on…

Solar and Stellar Astrophysics · Physics 2015-05-14 Stefan Uttenthaler , Thomas Lebzelter

The abundances of alkali elements (Li, Na, and K) were determined from the Li I 6708, Na I 5682/5688, and K I 7699 lines by taking into account the non-LTE effect for 24 sharp-lined A-type stars v sin i < 50 km/s, 7000 K < Teff <10000 K,…

Solar and Stellar Astrophysics · Physics 2015-06-03 Yoichi Takeda , Dong-Il Kang , Inwoo Han , Byeong-Cheol Lee , Kang-Min Kim , Satoshi Kawanomoto , Naoko Ohishi

As a test of rotationally-induced mixing causing the well-known Li dip in older mid-F dwarfs in the local Galactic disk, we utilize high-resolution and -S/N Keck/HIRESspectroscopy to measure the Li abundance in the components of the1 Gyr,…

Solar and Stellar Astrophysics · Physics 2015-06-16 Patrick Baugh , Jeremy R. King , Constantine P. Deliyannis , Ann Merchant Boesgaard

The observed amount of lithium for low metallicity population II stars (known as the Spite plateau) is a factor of $\sim 3-5$ lower than the predictions of the standard cosmology. Since the observations are limited to the local Universe…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-06 Maxim Pospelov , Niayesh Afshordi

We aim to constrain the mixing processes in low-mass stars by investigating the behaviour of the Li surface abundance after the main sequence. We take advantage of the data from the sixth internal data release of Gaia-ESO, idr6, and from…

Lithium abundance in most of the warm metal-poor main sequence stars shows a constant plateau (A(Li)~2.2 dex) and then the upper envelope of the lithium vs. metallicity distribution increases as we approach solar metallicity. Meteorites,…

Li abundances in the bulk of low-mass metal-poor stars are well reproduced by stellar evolution models adopting a constant initial abundance. However, a small number of stars have exceptionally high Li abundances, for which no convincing…

Solar and Stellar Astrophysics · Physics 2018-01-31 Haining Li , Wako Aoki , Tadafumi Matsuno , Yerra Bharat Kumar , Jianrong Shi , Takuma Suda , Gang Zhao

The lithium abundance in 62 halo dwarfs is determined from accurate equivalent widths reported in the literature and an improved infrared flux method (IRFM) temperature scale. The Li abundance of 41 plateau stars (those with Teff > 6000 K)…

Astrophysics · Physics 2009-11-10 Jorge Melendez , Ivan Ramirez

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

Lithium abundances, radial velocities and rotational velocities are reported for 20 candidate F, G and K stars of the sparse Coma Berenices open cluster. All the stars are proper-motion selected, and our radial velocities support the…

Astrophysics · Physics 2009-11-06 A. Ford , R. D. Jeffries , D. J. James , J. R. Barnes

This paper presents the chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Aluminium and Lithium abundances were derived through spectral…

Solar and Stellar Astrophysics · Physics 2022-02-09 J. Schiappacasse-Ulloa , S. Lucatello , M. J. Rain , A. Pietrinferni

The existence of one percent of lithium-rich giant stars among normal, lithium-poor giant stars continues to be poorly explained. By merging two catalogues, one containing 10,535 lithium-rich giant stars with lithium abundances ranging from…

Solar and Stellar Astrophysics · Physics 2024-12-09 R. de la Reza

We discuss the current status of the sample of Lithium abundances in extremely metal poor (EMP) turn-off (TO) stars collected by our group, and compare it with the available literature results. In the last years, evidences have accumulated…

Solar and Stellar Astrophysics · Physics 2012-07-02 L. Sbordone , P. Bonifacio , E. Caffau

In this work, we studied the distribution of lithium abundances in giants as a function of stellar mass. We used a sample of 1240 giants common among Kepler photometric and LAMOST medium resolution (R $\approx$ 7500) spectroscopic survey…

Solar and Stellar Astrophysics · Physics 2023-02-13 Anohita Mallick , Raghubar Singh , Bacham E. Reddy

About one percent of giants\upcite{Brown1989} are detected to have anomalously high lithium (Li) abundances in their atmospheres, conflicting directly with the prediction of the standard stellar evolution models\upcite{Iben1967}, and making…

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

This study investigates the temporal and spatial variations in lithium abundance within the Milky Way using a sample of 22,034 main-sequence turn-off (MSTO) stars and subgiants, characterised by precise stellar ages, 3D NLTE (non-local…

Astrophysics of Galaxies · Physics 2024-11-21 Tiancheng Sun , Shaolan Bi , Xunzhou Chen , Yuxi , Lu , Yuqin Chen , Ming-Yi Ding , Jianrong Shi , Hongliang Yan , Zhishuai Ge
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