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相关论文: Lithium Abundances in a Sample of Planet Hosting D…

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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 ~…

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…

太阳与恒星天体物理 · 物理学 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

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

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…

Lithium abundances in a sample of halo dwarfs have been redetermined by using the new T$_{eff}$ derived by Fuhrmann et al (1994) from modelling of the Balmer lines. These T$_{eff}$ are reddening independent, homogeneous and of higher…

天体物理学 · 物理学 2007-05-23 P. Molaro , F. Primas , P. Bonifacio

Abundances of lithium, carbon, and oxygen have been derived using spectral synthesis for a sample of 249 bright F, G, and K Northern Hemisphere dwarf stars from the high-resolution spectra acquired with the VUES spectrograph at the Moletai…

Of all the light elements, lithium is the most sensitive indicator of stellar evolution. This review discusses current data on the abundance of lithium in the atmospheres of A-, F-, G-, and K-stars of different types, as well as the…

太阳与恒星天体物理 · 物理学 2017-01-23 L. S. Lyubimkov

We present a non-local thermodynamic equilibrium abundance analysis of the resonance doublet Li I at 6707.8 A for 55 Galactic F and G supergiants and bright giants. The derived lithium abundances log \epsilon(Li) may be considered in three…

We have determined Li abundances in 55 metal-poor (3.6 < [Fe/H] < -0.7) stars with extreme orbital kinematics. We find the Li abundance in the Li-plateau stars and examine its decrease in low-temperature, low-mass stars. The Li observations…

天体物理学 · 物理学 2009-11-13 Ann Merchant Boesgaard , Alex Stephens , Constantine P. Deliyannis

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

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

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…

天体物理学 · 物理学 2016-01-13 P. Molaro , P. Bonifacio , L. Pasquini

Planet engulfment has been identified as one of the mechanisms for enhancing lithium abundance in stars. However, comprehensive investigations into lithium signatures following such events remain limited. Stars born together, sharing a…

We investigate the distribution of the lithium abundances, A(Li), of metal-poor dwarf and subgiant stars within the limits 5500 K < Teff < 6700 K, -6.0 < [Fe/H] < -1.5, and logg > ~3.5 (a superset of parameters first adopted by Spite and…

太阳与恒星天体物理 · 物理学 2023-04-05 J. E. Norris , D. Yong , A. Frebel , S. G. Ryan

One of the most important factors in determining the stellar lithium abundance is the effective temperature. In a previous study by the authors, new effective temperatures Teff for sixteen metal-poor halo dwarfs were derived using a local…

太阳与恒星天体物理 · 物理学 2015-05-18 A. Hosford , A. E. Garcia Perez , R. Collet , S. G. Ryan , J. E. Norris , K. A. Olive

The prediction of the PLANCK-constrained primordial lithium abundance in the Universe is in discordance with the observed Li abundances in warm Population II dwarf and subgiant stars. Among the physically best motivated ideas, it has been…

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…

Rapidly growing datasets from stellar spectroscopic surveys are providing unprecedented opportunities to analyse the chemical evolution history of our Galaxy. However, spectral analysis requires accurate modelling of synthetic stellar…

太阳与恒星天体物理 · 物理学 2024-03-29 J. W. E. Mallinson , K. Lind , A. M. Amarsi , K. Youakim

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…

太阳与恒星天体物理 · 物理学 2022-06-01 A. Mucciarelli , L. Monaco , P. Bonifacio , M. Salaris , M. Deal , M. Spite , O. Richard , R. Lallement

Lithium is extensively known to be a good tracer of non-standard mixing processes occurring in stellar interiors. We present the results of a new large Lithium survey in red giant stars and combine it with surveys from the literature to…

太阳与恒星天体物理 · 物理学 2020-01-08 C. Charbonnel , N. Lagarde , G. Jasniewicz , P. North , M. Shetrone , J. Krugler Hollek , V. V. Smith , R. Smiljanic , A. Palacios , G. Ottoni