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Related papers: Pre-main-sequence Lithium Depletion

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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…

Astrophysics · Physics 2009-11-07 Eduardo L. Martin , Gibor Basri , Yakiv Pavlenko , Yuri Lyubchik

(Abridged) We contribute to our understanding of the evolution of young intermediate-mass stars by providing a comprehensive analysis of their lithium (Li) content. A sample of 71 intermediate-mass T Tauri (IMTT) and Herbig stars within the…

Low-mass stars play a key role in many different areas of astrophysics. In this article, I provide a brief overview of the evolution of low-mass stars, and discuss some of the uncertainties and problems currently affecting low-mass stellar…

Solar and Stellar Astrophysics · Physics 2015-06-12 M. Catelan

The vast majority of stars with mass similar to the Sun are expected to only destroy lithium over the course of their lives, via low-temperature nuclear burning. This has now been supported by observations of hundreds of thousands of red…

Solar and Stellar Astrophysics · Physics 2020-07-15 Yerra Bharat Kumar , Bacham E. Reddy , Simon W. Campbell , Sunayana Maben , Gang Zhao , Yuan-Sen Ting

Pre-main sequence (PMS) stars evolve into main sequence (MS) phase over a period of time. Interestingly, we found a scarcity of studies in existing literature that examines and attempts to better understand the stars in PMS to MS transition…

Solar and Stellar Astrophysics · Physics 2021-09-01 Suman Bhattacharyya , Blesson Mathew , Gourav Banerjee , R. Anusha , KT Paul , Sreeja S Kartha

As part of a long term effort to understand pre-main sequence Li burning, we have obtained high resolution spectroscopic observations of 14 late type stars (G0--M1) in the young open cluster IC~4665. Most of the stars have \ha filled-in and…

Astrophysics · Physics 2016-08-30 E. L. Martin , D. Montes

The question of the existence of pre-main sequence (PMS) $\gamma$~Doradus ($\gamma$~Dor) has been raised by the observations of young clusters such as NGC~884 hosting $\gamma$~Dor members. We have explored the properties of $\gamma$~Dor…

Solar and Stellar Astrophysics · Physics 2015-05-19 M. -P. Bouabid , J. Montalbán , A. Miglio , M. -A. Dupret , A. Grigahcène , A. Noels

We present extensive calculations of the structure and the evolution of low-massstars in the range 0.07-0.8 $\msol$, for metallicities $-2.0\le \mh \le 0.0$. These calculations are based on the most recent description of the microphysics…

Astrophysics · Physics 2008-11-26 Gilles Chabrier , Isabelle Baraffe

Eclipsing binaries with M-type components are still rare objects. Strong observational biases have made that today only a few eclipsing binaries with component masses below 0.6 Msun and well-determined fundamental properties are known.…

Astrophysics · Physics 2009-11-11 Ignasi Ribas

High-resolution CTIO 4-m/HYDRA spectroscopy of the super-metal-rich open cluster NGC 6253 ([Fe/H]=+0.43+/-0.01) has been used to study the stellar lithium (Li) abundances near the cluster's turnoff. NGC 6253 greatly expands the range of…

Solar and Stellar Astrophysics · Physics 2015-06-11 Jeffrey D. Cummings , Constantine P. Deliyannis , Barbara Anthony-Twarog , Bruce Twarog , Ryan M. Maderak

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…

Astrophysics · Physics 2009-11-10 Garik Israelian , Nuno Santos , Michel Mayor , Rafael Rebolo

To alleviate the discrepancy between the prediction of the primordial lithium abundance in the universe and the abundances observed in Pop II dwarfs and subgiant stars, it has been suggested that the stars observable today have undergone…

Solar and Stellar Astrophysics · Physics 2015-05-13 K. Lind , F. Primas , C. Charbonnel , F. Grundahl , M. Asplund

Absorption features in stellar atmospheres are often used to calibrate photocentric velocities for kinematic analysis of further spectral lines. The Li feature at $\sim$ 6708 {\AA} is commonly used, especially in the case of young stellar…

We have performed evolutionary calculations of very-low-mass stars from 0.08 to 0.8 $\msol$ for different metallicites from [M/H]= -2.0 to -1.0 and we have tabulated the mechanical, thermal and photometric characteristics of these models.…

Astrophysics · Physics 2010-04-06 Isabelle Baraffe , Gilles Chabrier , France Allard , Peter Hauschildt

We have derived accurate and homogeneous Lithium abundances in 49 main sequence binary systems belonging to the Hyades Open Cluster by using a deconvolution method to determine individual magnitudes and colors for the primary and secondary…

Astrophysics · Physics 2007-05-23 D. Barrado y Navascues , J. R. Stauffer

We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…

Astrophysics · Physics 2016-08-30 Carlos Abia , Lyudmila Mashonkina

The theory of substellar evolution predicts that there is a sharp mass boundary between lithium and non-lithium brown dwarfs, not far below the substellar-mass limit. The imprint of thermonuclear burning is carved on the surface lithium…

Solar and Stellar Astrophysics · Physics 2021-11-03 Eduardo L. Martín , Nicolas Lodieu , Carlos del Burgo

A thorough study of the effects of mass loss on internal and surface abundances of A and F stars is carried out in order to constrain mass loss rates for these stars, as well as further elucidate some of the processes which compete with…

Solar and Stellar Astrophysics · Physics 2015-05-19 Mathieu Vick , Georges Michaud , Jacques Richer , Olivier Richard

Studies of beryllium abundance in large samples of solar-type stars show a small fraction of extremely beryllium-deficient stars, which challenges our current understanding of light element depletion in these stars. We suggest two possible…

Solar and Stellar Astrophysics · Physics 2015-06-11 M. Viallet , I. Baraffe

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…

Solar and Stellar Astrophysics · Physics 2016-02-24 Marilia Carlos , Poul E. Nissen , Jorge Melendez
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