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相关论文: A Comparative Study on Lithium Abundances in Solar…

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We present a comparison of the lithium abundances of stars with and without planetary-mass companions. New lithium abundances are reported in 79 planet hosts and 38 stars from a comparison sample. When the Li abundances of planet host stars…

天体物理学 · 物理学 2009-11-10 Garik Israelian , Nuno Santos , Michel Mayor , Rafael Rebolo

Recent observational work by Israelian et al. has shown that sun-like planet host stars in the temperature range 5700K < Teff < 5850K have lithium abundances that are significantly lower than those observed for "single" field stars. In this…

太阳与恒星天体物理 · 物理学 2015-05-18 S. G. Sousa , J. Fernandes , G. Israelian , N. C. Santos

The surface abundance of lithium on the Sun is 140 times less than protosolar, yet the temperature at the base of the surface convective zone is not hot enough to burn Li. A large range of Li abundances in solar type stars of the same age,…

We compare the Li abundances of a sample of stars with planets discovered with the Doppler method to a sample of stars without detected planets. We prepared the samples by combining the Li abundances reported in several recent studies in a…

天体物理学 · 物理学 2009-11-13 Guillermo Gonzalez

The lithium abundances of planet-harbouring stars have been compared with those of open clusters and field stars. Young (chromospherically active) and subgiant stars have been eliminated from the comparison because they are at different…

天体物理学 · 物理学 2009-10-31 Sean G. Ryan

We have determined precise stellar parameters and lithium abundances in a sample of 117 stars with basic properties very similar to the Sun. This sample selection reduces biasing effects and systematic errors in the analysis. We estimate…

太阳与恒星天体物理 · 物理学 2015-05-19 Patrick Baumann , Iván Ramírez , Jorge Meléndez , Martin Asplund , Karin Lind

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…

天体物理学 · 物理学 2009-11-07 J. Montalban , R. Rebolo

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…

This work presents a homogeneous determination of lithium abundances in a large sample of giant-planet hosting stars (N=117), and a control sample of disk stars without detected planets (N=145). The lithium abundances were derived using a…

太阳与恒星天体物理 · 物理学 2010-11-04 L. Ghezzi , K. Cunha , V. V. Smith , R. de la Reza

We want to determine the lithium abundances of solar twin stars as a function of stellar age to provide constraints for stellar evolutions models and to investigate whether there is a connection between low Li abundance and the occurrence…

太阳与恒星天体物理 · 物理学 2016-02-24 Marilia Carlos , Poul E. Nissen , Jorge Melendez

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite…

天体物理学 · 物理学 2009-11-11 Ann Merchant Boesgaard , Megan C. Novicki , Alex Stephens

We present a survey of lithium abundances in 185 main- sequence field stars with Teff between 5600 and 6600 K and [Fe/H] from -1.4 to +0.2 based on high-resolution spectra of 130 stars and a reanalysis of data from Lambert et al. (1991).…

天体物理学 · 物理学 2009-11-06 Y. Q. Chen , P. E. Nissen , T. Benoni , G. Zhao

We have derived beryllium abundances in a wide sample of stars hosting planets, with spectral types in the range F7V-K0V, aimed at studying in detail the effects of the presence of planets on the structure and evolution of the associated…

Lithium is an excellent tracer of mixing in stars as it is destroyed (by nuclear reactions) at a temperature around $\sim 2.5\times 10^6$ K. The lithium destruction zone is typically located in the radiative region of a star. If the…

天体物理学 · 物理学 2007-05-23 Brian Chaboyer

The lithium present in the photospheres of solar-type stars is transported to the inner parts by convection, reaching regions even somewhat below the convection zone, by non-standard transport mechanisms. In stars with deeper convective…

太阳与恒星天体物理 · 物理学 2023-05-04 Giulia Martos , Jorge Meléndez , Anne Rathsam , Gabriela Carvalho Silva

We derive atmospheric parameters and lithium abundances for 671 stars and include our measurements in a literature compilation of 1381 dwarf and subgiant stars. First, a "lithium desert" in the effective temperature (Teff) versus lithium…

太阳与恒星天体物理 · 物理学 2015-06-05 I. Ramirez , J. R. Fish , D. L. Lambert , C. Allende Prieto

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…

天体物理学 · 物理学 2009-11-10 Avi M. Mandell , Jian Ge , Norm Murray

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…

太阳与恒星天体物理 · 物理学 2015-06-19 Y. J. Liu , K. F. Tan , L. Wang , G. Zhao , Bun'ei Sato , Y. Takeda , H. N. Li

Lithium depletion and enrichment in the cosmos is not yet well understood. To help tighten constraints on stellar and Galactic evolution models, we present the largest high-resolution analysis of Li abundances A(Li) to date, with results…

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,…

天体物理学 · 物理学 2009-10-31 Jeremy King , Anita Krishnamurthi , Marc H. Pinsonneault
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