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Related papers: Lithium isotopes in population II dwarfs

200 papers

We present an analytic calculation of the thermonuclear depletion of lithium in contracting, fully convective, pre-main sequence stars of mass M < 0.5 M_sun. Previous numerical work relies on still-uncertain physics (atmospheric opacities…

Astrophysics · Physics 2009-10-28 Lars Bildsten , Edward F. Brown , Christopher D. Matzner , Greg Ushomirsky

We have determined Li abundances for eleven metal-poor turn-off stars, among which eight have [Fe/H]<-3, based on LTE analyses of high-resolution spectra obtained with the HDS on the Subaru telescope. The Li abundances for four of these…

We have used two robotic telescopes to obtain time-series high-resolution spectroscopy and V I and/or by photometry for a sample of 60 active stars. Orbital solutions are presented for 26 SB2 and 19 SB1 systems with unprecedented phase…

Solar and Stellar Astrophysics · Physics 2015-06-11 K. G. Strassmeier , M. Weber , T. Granzer , S. Järvinen

The aim of the present study is to determine the Li abundances for a large set of the FGK dwarfs and to analyse the connections between the Li content, stellar parameters, and activity. Atmospheric parameters, rotational velocities and Li…

Solar and Stellar Astrophysics · Physics 2015-06-11 T. V. Mishenina , C. Soubiran , V. V. Kovtyukh , M. M. Katsova , M. A. Livshits

We present high-resolution and high-quality UVES spectroscopic data of the metal-poor double-lined spectroscopic binary CS 22876--032 ([Fe/H] $\sim -3.7$ dex), with the goal to derive the $^6$Li/$^7$Li isotopic ratio by analysing the…

Solar and Stellar Astrophysics · Physics 2019-08-14 J. I. González Hernández , P. Bonifacio , E. Caffau , H. G. Ludwig , M. Steffen , L. Monaco , R. Cayrel

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

A search for lithium is performed on seven metal poor dwarfs with metallicities ranging from [Fe/H]=-1.5 down to [Fe/H]=-3.0 but showing disk-like kinematics. These stars belong to the metal poor tail of the Galactic thick disk and they may…

Astrophysics · Physics 2016-01-13 P. Molaro , P. Bonifacio , L. Pasquini

The evolution of lithium abundance over a star's lifetime is indicative of transport processes operating in the stellar interior. We revisit the relationship between lithium content and rotation rate previously reported for cool dwarfs in…

Solar and Stellar Astrophysics · Physics 2018-06-13 J. Bouvier , D. Barrado , E. Moraux , J. Stauffer , L. Rebull , L. Hillenbrand , A. Bayo , I. Boisse , H. Bouy , E. DiFolco , J. Lillo-Box , M. Morales Calderon

We report results from lithium abundance determinations using high resolution spectral analysis of the 107 metal-rich stars from the Calan-Hertfordshire Extrasolar Planet Search programme. We set out to understand the lithium distribution…

Solar and Stellar Astrophysics · Physics 2018-03-21 Ya. V. Pavlenko , J. S. Jenkins , O. M. Ivanyuk , H. R. A. Jones , B. M. Kaminsky , Yu. P. Lyubchik , L. A. Yakovina

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 surface lithium abundance A(Li) of warm metal-poor dwarf stars exhibits a narrow plateau down to [Fe/H]~-2.8 dex, while at lower metallicities the average value drops by 0.3 dex with a significant star-by-star scatter (called lithium…

Solar and Stellar Astrophysics · Physics 2022-06-01 A. Mucciarelli , L. Monaco , P. Bonifacio , M. Salaris , M. Deal , M. Spite , O. Richard , R. Lallement

A highly homogeneous study of 23 halo field dwarf stars has achieved a Li abundance accuracy of 0.033 dex per star. The work shows that the intrinsic spread of the Li abundances of these stars at a given metallicity is <0.02 dex, and…

Astrophysics · Physics 2007-05-23 Sean G. Ryan

[ABRIDGED] We determine Li abundances for a well-studied sample of 714 F and G dwarf, turn-off, and subgiant stars in the solar neighbourhood. The analysis is based on line synthesis of the Li line at 6707 {\AA} in high-resolution and high…

Astrophysics of Galaxies · Physics 2018-08-01 Thomas Bensby , Karin Lind

The lithium-dip observed in mid-F dwarfs remains a long-standing challenge for stellar evolution models. We present high-precision stellar parameters and A(Li) for 22 new comoving pairs, primarily located on the hotter side of the Li-Dip.…

Solar and Stellar Astrophysics · Physics 2025-08-14 Qinghui Sun , Yuan-Sen Ting , Barbara J. Anthony-Twarog , Bruce A. Twarog , Fan Liu , Yuxi , Lu

We employ a new Infrared Flux Method (IRFM) temperature scale (Ramirez & Melendez 2005, ApJ 626, 446; ApJ 626, 465) in order to determine Li, O, and Fe NLTE abundances in a sample of relatively unevolved (dwarfs, turn-off, subgiants)…

Astrophysics · Physics 2009-11-11 Jorge Melendez , Nataliya G. Shchukina , Ivan Ramirez , Irina Vasiljeva

The "stellar" solution to the cosmological lithium problem proposes that surface depletion of lithium in low-mass, metal-poor stars can reconcile the lower abundances found for Galactic halo stars with the primordial prediction. Globular…

Solar and Stellar Astrophysics · Physics 2015-05-18 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund

We present Li abundances for 73 stars in the metallicity range -3.5 < [Fe/H] < -1.0 using improved IRFM temperatures (Casagrande et al. 2010) with precise E(B-V) values obtained mostly from interstellar NaI D lines, and high-quality…

Solar and Stellar Astrophysics · Physics 2015-05-14 J. Melendez , L. Casagrande , I. Ramirez , M. Asplund , W. J. Schuster

We have performed a new and homogeneous analysis of all the Li data available in the literature for main sequence stars (spectral-types from late F to K) in open clusters. In the present paper we focus on a detailed investigation of MS Li…

Astrophysics · Physics 2009-11-11 P. Sestito , S. Randich

We present the results of a spectroscopic survey of X-ray selected, low-mass candidate members of the young open cluster NGC 2547. Using a combination of photometry, spectroscopic indices and radial velocities we refine our candidate list…

Astrophysics · Physics 2009-11-07 R. D Jeffries , J. M. Oliveira , D. Barrado y Navascues , J. R. Stauffer

We present Li and Fe abundances for 87 stars in the GC M4,obtained with GIRAFFE high-resolution spectra. The targets range from the TO up to the RGB Bump. The Li abundance in the TO stars is uniform, with an average value A(Li)=2.30+-0.02…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Mucciarelli , M. Salaris , L. Lovisi , F. R. Ferraro , L. Lanzoni , S. Lucatello , R. G. Gratton
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