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相关论文: Metallicity and age effects on lithium depletion i…

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The main goal of this work is to evaluate the correlation between Li abundance, age, and mass. Using high-quality ESO/HARPS data (R $\simeq$ 115 000; 270 $\leq$ SNR $\leq$ 1000), we measured Li abundances via spectral synthesis of the…

太阳与恒星天体物理 · 物理学 2023-09-15 Anne Rathsam , Jorge Meléndez , Gabriela Carvalho Silva

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 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 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…

The present work aims to examine in detail the depletion of lithium in solar twins to better constrain stellar evolution models and investigate its possible connection with exoplanets. We employ spectral synthesis in the region of the…

太阳与恒星天体物理 · 物理学 2019-03-20 M. Carlos , J. Melendez , L. Spina , L. A. dos Santos , M. Bedell , I. Ramirez , M. Asplund , J. L. Bean , D. Yong , J. Yana Galarza , A. Alves-Brito

We examine the internal structure of solar-like stars in detail between 0.8 and 1.4M Sun and during pre-main sequence phase. Recent opacity computations of OPAL along with a new hydrodynamical mixing process have been considered. We also…

天体物理学 · 物理学 2008-11-26 L. Piau , S. Turck-Chieze

We have investigated the abundance anomalies of lithium for stars with planets in the temperature range of 5600--5900 K reported by Israelian and coworkers, as compared to 20 normal stars at the same temperature and metallicity ranges. Our…

天体物理学 · 物理学 2010-11-11 Y. Q. Chen , G. Zhao

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

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…

太阳与恒星天体物理 · 物理学 2015-05-19 J. D. do Nascimento , J. S. da Costa , J. R. De Medeiros

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

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 study lithium depletion in low-mass and solar-like stars as a function of time, using a new diffusion coefficient describing extra-mixing taking place at the bottom of a convective envelope. This new form is motivated by…

太阳与恒星天体物理 · 物理学 2017-08-16 I. Baraffe , J. Pratt , T. Goffrey , T. Constantino , D. Folini , M. V. Popov , R. Walder , M. Viallet

We present high-resolution spectroscopic observations of the \ion{Li}{1} resonance line in a sample of 62 stars that belong to 31 common-proper motion pairs with twin F or G-type components. Photospheric abundances of lithium were derived…

天体物理学 · 物理学 2009-11-07 Eduardo L. Martin , Gibor Basri , Yakiv Pavlenko , Yuri Lyubchik

We propose here that the lithium decrease at super-solar metallicities observed in high resolution spectroscopic surveys can be explained by the interplay of mixed populations, coming from the inner regions of the Milky Way disc. The lower…

星系天体物理 · 物理学 2019-03-13 G. Guiglion , C. Chiappini , D. Romano , F. Matteucci , F. Anders , M. Steinmetz , I. Minchev , P. de Laverny , A. Recio-Blanco

The surface content of lithium (Li) and beryllium (Be) in stars can reveal important information about the temperature structure and physical processes in their interior regions. This study focuses on solar-type stars with a sample that is…

太阳与恒星天体物理 · 物理学 2022-12-14 Ann Merchant Boesgaard , Constantine P. Deliyannis , Michael G. Lum , Ashley Chontos

We report the discovery of a peculiar set of old super-metal-rich dwarf stars with orbits of low eccentricity that reach a maximum height from the Galactic plane between $\sim$ 0.5-1.5 kpc observed by the \emph{Gaia}-ESO Survey. These stars…

太阳与恒星天体物理 · 物理学 2025-01-29 M. L. L. Dantas , R. Smiljanic , R. Boesso , H. Rocha-Pinto , L. Magrini , G. Guiglion , D. Romano

Transport processes occurring in the radiative interior of solar-type stars are evidenced by the surface variation of light elements, in particular Li, and the evolution of their rotation rates. For the Sun, inversions of helioseismic data…

太阳与恒星天体物理 · 物理学 2021-02-10 T. Dumont , A. Palacios , C. Charbonnel , O. Richard , L. Amard , K. Augustson , S. Mathis

The behavior of lithium (Li) in Population I main sequence stars challenges standard stellar theory. Two phenomena stand out: the solar Li problem which extends to Li depletion in solar analogs and the Li dip observed in mid-F stars within…

太阳与恒星天体物理 · 物理学 2025-08-28 Xuefeng Li , Jianrong Shi , Yan Li , Hongliang Yan , Jinghua Zhang

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 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…

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