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Related papers: Lithium Depletion in Fully Convective Pre-Main Seq…

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Aims. This study aims to determine the level and constancy of the Spite plateau as definitively as possible from homogeneous high-quality VLT-UVES spectra of 19 of the most metal-poor dwarf stars known. Methods. Our high-resolution (R ~…

Rotational mixing is a prime candidate for explaining the gradual depletion of lithium from the photospheres of cool stars during the main sequence. However, previous mixing calculations have relied primarily on treatments of angular…

Solar and Stellar Astrophysics · Physics 2016-09-28 Garrett Somers , Marc H. Pinsonneault

We report on the abundance analysis of Li in solar-type (G-type main sequence) superflare stars which were found by the analysis of Kepler photometric data. Li is a key element to understand the evolution of the stellar convection zone…

Solar and Stellar Astrophysics · Physics 2015-07-15 Satoshi Honda , Yuta Notsu , Hiroyuki Maehara , Shota Notsu , Takuya Shibayama , Daisaku Nogami , Kazunari Shibata

We present novel tests of pre$-$main-sequence models based on individual dynamical masses for the M7 binary LSPM J1314+1320AB. Joint analysis of our Keck adaptive optics astrometric monitoring along with Very Long Baseline Array radio data…

Solar and Stellar Astrophysics · Physics 2016-08-17 Trent J. Dupuy , Jan Forbrich , Aaron Rizzuto , Andrew W. Mann , Kimberly Aller , Michael C. Liu , Adam L. Kraus , Edo Berger

Observational constraints on the primordial lithium abundance are important for the evaluation of the baryonic density of the universe. Its precise determination however suffers from uncertainties due to the possible depletion of this…

Astrophysics · Physics 2009-10-30 Sylvie Vauclair , Corinne Charbonnel

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

Lithium abundances are presented and discussed for 70 members of the 50 Myr old open cluster alpha Per. More than half of the abundances are from new high-resolution spectra. The Li abundance in the F-type stars is equal to its presumed…

Solar and Stellar Astrophysics · Physics 2015-05-19 Suchitra C. Balachandran , Sushma V. Mallik , David L. Lambert

Rotational velocity, lithium abundance, and the mass depth of the outer convective zone are key parameters in the study of the processes at work in the stellar interior, in particular when examining the poorly understood processes operating…

Solar and Stellar Astrophysics · Physics 2015-05-19 J. D. do Nascimento , J. S. da Costa , J. R. De Medeiros

The primordial Lithium Problem is intimately connected to the assumption that ${}^{7}{\rm Li}$ observed in metal-poor halo stars retains its primordial abundance, which lies significantly below the predictions of standard big-bang…

Astrophysics of Galaxies · Physics 2022-04-08 Brian D. Fields , Keith A. Olive

We assess the impact of starspots on the evolution of late-type stars during the pre-main sequence (pre-MS) using a modified stellar evolution code. We find that heavily spotted models of mass 0.1-1.2\msun\ are inflated by up to $10$%…

Solar and Stellar Astrophysics · Physics 2015-07-15 Garrett Somers , Marc H. Pinsonneault

Lithium abundances in open clusters are a very effective probe of mixing processes, and their study can help to understand the large depletion of lithium in the Sun. Due to its age and metallicity, the open cluster M67 is especially…

Solar and Stellar Astrophysics · Physics 2015-06-04 Giancarlo Pace , Matthieu Castro , Jorge Melendez , Sylvie Theado , Jose-Dias do Nascimento

We want to study the effects of the formation of planets and planetary systems on the atmospheric Li abundance of planet host stars. In this work we present new determinations of lithium abundances for 326 Main Sequence stars with and…

Abundance measurements of the light elements lithium, beryllium, and boron are playing an increasingly important role in the study of stellar physics. Because these elements are easily destroyed in stars at temperatures 2--4 million K, the…

Astrophysics · Physics 2009-10-30 Edward F. Brown

We determine the surface lithium abundance of the eclipsing binary components in V 505 Per (HIP 10961), A(Li)=2.65+/-0.07 and 2.35+/-0.1, which supports the rather unexpected conclusion that their surface Li abundances differ. We find…

Solar and Stellar Astrophysics · Physics 2025-07-29 G. Koenigsberger , W. Schmutz , C. Pilachowski , A. R. Mejia-Nava , D. Sikorski , M. Cordero

We present results from new, detailed computations of lithium production by hot bottom burning (HBB) in asymptotic giant branch (AGB) stars of intermediate mass. The dependance of lithium production on stellar mass, metallicity, mass loss…

Astrophysics · Physics 2007-05-23 I. Mazzitelli , F. D'Antona , P. Ventura

Lithium abundances in open clusters provide an effective way of probing mixing processes in the interior of solar-type stars and convection is not the only mixing mechanism at work. To understand which mixing mechanisms are occurring in…

Solar and Stellar Astrophysics · Physics 2016-05-25 Matthieu Castro , Tharcísyo Duarte , Giancarlo Pace , José Dias do Nascimento

The lithium abundances for 378 G/K giants are derived with non-LTE correction considered. Among these, there are 23 stars that host planetary systems. The lithium abundance is investigated, as a function of metallicity, effective…

Solar and Stellar Astrophysics · Physics 2015-06-19 Y. J. Liu , K. F. Tan , L. Wang , G. Zhao , Bun'ei Sato , Y. Takeda , H. N. Li

We have obtained new photometry and intermediate resolution ($\Delta \lambda = 2.7$ \AA\ ) spectra of 19 of these objects (14.9 $\le$ $I_c$ $\le$ 17.5) in order to confirm cluster membership. We identify 15 of our targets as likely cluster…

Astrophysics · Physics 2011-02-11 D. Barrado y Navascues , J. R. Stauffer , B. M. Patten

We have used medium resolution spectra to search for evidence that proto-stellar objects accrete at high rates during their early 'assembly phase'. Models predict that depleted lithium and reduced luminosity in T-Tauri stars are key…

Astrophysics of Galaxies · Physics 2015-06-16 Darryl J. Sergison , N. J. Mayne , Tim Naylor , R. D. Jeffries , Cameron P. M. Bell

Evolution of the 7Li abundance in the convection zone of the Sun during different stages of its life time is considered to explain its low photospheric value in comparison with that of the solar system meteorites. Lithium is intensively and…

Solar and Stellar Astrophysics · Physics 2017-02-01 F. Thevenin , A. V. Oreshina , V. A. Baturin , A. B. Gorshkov , P. Morel , J. Provost