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We compare the properties of recent samples of the lithium abundances in halo stars to one another and to the predictions of theoretical models including rotational mixing, and we examine the data for trends with metal abundance. We find…

Astrophysics · Physics 2008-11-26 M. H. Pinsonneault , G. Steigman , T. P. Walker , V. K. Narayanan

Lithium is a fragile but crucial chemical element in the universe, exhibits interesting and complex behaviors. Thanks to the massive spectroscopic data from the Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST)…

The dispersion in lithium abundance at fixed effective temperature in young cool stars like the Pleiades has proved a difficult challenge for stellar evolution theory. We propose that Li abundances relative to a mean temperature trend,…

Astrophysics · Physics 2009-10-31 Jeremy King , Anita Krishnamurthi , Marc H. Pinsonneault

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 abundance patterns of metal-poor stars provide us a wealth of chemical information about various stages of the chemical evolution of the Galaxy. In particular, these stars allow us to study the formation and evolution of the elements…

Astrophysics · Physics 2008-02-15 Anna Frebel

Realistic 3-dimensional (3D), radiative hydrodynamical surface convection simulations of the metal-poor halo stars HD 140283 and HD 84937 have been performed. Due to the dominance of adiabatic cooling over radiative heating very low…

Astrophysics · Physics 2007-05-23 M. Asplund , AA. Nordlund , R. Trampedach , R. F. Stein

We test a scenario in which radial migration could affect the Li abundance pattern of dwarf stars in the solar neighbourhood. This may confirm that the Li abundance in these stars can not serve as a probe for the Li abundance in the…

The recent discovery of a hyper metal-poor (HMP) star, whose metallicity Fe/H is smaller than 1/100,000 of the solar ratio, together with one earlier HMP star, has raised a challenging question if these HMP stars are the actual first…

Astrophysics · Physics 2009-11-11 Nobuyuki Iwamoto , Hideyuki Umeda , Nozomu Tominaga , Ken'ichi Nomoto , Keiichi Maeda

Aims. We study the impact of the presence of planets on the lithium abundance of host stars and evaluate the previous claim that planet hosts exhibit lithium depletion when compared to their non-host counterparts. Methods. Using previously…

Earth and Planetary Astrophysics · Physics 2014-10-15 P. Figueira , J. P. Faria , E. Delgado-Mena , V. Zh. Adibekyan , S. G. Sousa , N. C. Santos , G. Israelian

The cosmological lithium problem, that is, the discrepancy between the lithium abundance predicted by the Big Bang nucleosynthesis and the one observed for the stars of the 'Spite plateau', is one of the long standing problems of modern…

Solar and Stellar Astrophysics · Physics 2020-07-01 E. Tognelli , P. G. Prada Moroni , S. Degl'Innocenti , M. Salaris , S. Cassisi

The $^6$Li abundance observed in metal poor halo stars exhibits a plateau similar to that for $^7$Li suggesting a primordial origin. However, the observed abundance of $^6$Li is a factor of $10^3$ larger and that of $^7$Li is a factor of 3…

Planet accretion onto solar type stars may significantly change the stellar atmospheric abundances of 6Li and 7Li if it takes place after the star has arrived at the main sequence. Ingestion of planets at an earlier phase will not affect…

Astrophysics · Physics 2009-11-07 J. Montalban , R. Rebolo

The relationship between the respective depletion factors for 6Li and 7Li in metal-poor stars is studied for two simple models of depletion by nuclear burning by mixing with deeper layers, below the bottom of the convective zone. The…

Astrophysics · Physics 2009-10-31 R. Cayrel , Y. Lebtreton , P. Morel

A broad array of interstellar absorption features that appear in the ultraviolet spectra of bright sources allows us to measure the abundances and ionization states of many important heavy elements that exist as free atoms in the…

Astrophysics · Physics 2007-05-23 Edward B. Jenkins

We find that hot jupiter host stars within the T$_\mathrm{eff}$ range 5900-6300K show lower Li abundances, by 0.14 dex, than stars without detected planets. This offset has a significance at the level 7$\sigma$, pointing to a stronger…

In the multiple population framework, a number of studies have been accomplished in order to explore the behaviour of lithium with proton-capture element abundances (e.g., Na, O, Al) in globular cluster stars. Lithium offers perhaps one of…

Solar and Stellar Astrophysics · Physics 2020-06-19 Valentina D'Orazi , Raffaele Gratton

Precise Li abundances are determined for 54 giant stars mostly evolving across the Hertzsprung gap. We combine these data with rotational velocity and with information related to the deepening of the convective zone of the stars to analyse…

Astrophysics · Physics 2009-11-10 P. de Laverny , J. D. Jr do Nascimento , A. Lebre , J. R. De Medeiros

The orders of magnitude variation in lithium abundances of evolved stars have long been a puzzle. Diluted signals, ambiguous evolutionary states and unknown masses have made it challenging to both map the expected lithium signals and…

Solar and Stellar Astrophysics · Physics 2023-07-26 Jamie Tayar , Joleen K. Carlberg , Claudia Aguilera-Gómez , Maryum Sayeed

The observations of light elements in the Sun and Solar type stars give special clues for understanding the hydrodynamical processes at work in stellar interiors. In the Sun 7Li is depleted by 140 while 3He has not increased by more than…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair

The first generation of stars is quite unique. The absence of metals likely affects their formation, with current models suggesting a much more top-heavy initial mass fraction than what we observe today, and some of their other properties,…

Solar and Stellar Astrophysics · Physics 2020-02-13 Alexander Heger , Stan Woosley
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