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Related papers: The Galactic Lithium Evolution Revisited

200 papers

A LiBeB evolution model including Galactic Cosmic Ray nucleosynthesis, the $\nu$-process, novae, AGB and C-stars is presented. We have included Galactic Cosmic Ray Nucleosynthesis (GCRN) in a complete Chemical Evolution Model that takes…

Astrophysics · Physics 2016-11-03 Andreu Alibes , Javier Labay , Ramon Canal

Li abundances in the bulk of low-mass metal-poor stars are well reproduced by stellar evolution models adopting a constant initial abundance. However, a small number of stars have exceptionally high Li abundances, for which no convincing…

Solar and Stellar Astrophysics · Physics 2018-01-31 Haining Li , Wako Aoki , Tadafumi Matsuno , Yerra Bharat Kumar , Jianrong Shi , Takuma Suda , Gang Zhao

This contribution presents an overview of the evolution of Li abundances in stars of the Galactic thin and thick discs, from the observational point of view. The focus is on Li abundances obtained by recent projects and surveys. To separate…

Solar and Stellar Astrophysics · Physics 2020-06-23 Rodolfo Smiljanic

Preliminary abundances of lithium and a few other elements have been obtained for 31 field Am stars with good Hipparcos parallaxes, as well as for 36 normal A and F stars. Radial and projected rotational velocities were determined as well.…

Astrophysics · Physics 2009-11-11 P. North , F. Betrix , C. Besson

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

The predictions of Galactic chemical evolution models for D and $^3$He are described in connection with those on the other Galactic quantities for which observational constraints are available. Models in agreement with the largest set of…

Astrophysics · Physics 2007-05-23 Monica Tosi

In this Letter, we report on a low-resolution spectroscopic survey for Li-rich K giants among 2000 low mass (M <= 3 Msun) giants spanning the luminosity range from below to above the luminosity of the clump. Fifteen new Li-rich giants…

Solar and Stellar Astrophysics · Physics 2015-05-27 Yerra Bharat Kumar , Bacham E. Reddy , David L. Lambert

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

We measured $^{35}$Cl abundances in 52 M giants with metallicities between -0.5 $<$ [Fe/H] $<$ 0.12. Abundances and atmospheric parameters were derived using infrared spectra from CSHELL on the IRTF and from optical echelle spectra. We…

Solar and Stellar Astrophysics · Physics 2021-03-16 Z. G. Maas , C. A. Pilachowski

An overview of the sources for heavy elements in the early Galaxy is given. It is shown that observations of abundances in metal-poor stars can be used along with a basic understanding of stellar models to guide the search for the source of…

Astrophysics · Physics 2009-11-13 Yong-Zhong Qian

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…

Solar and Stellar Astrophysics · Physics 2015-06-05 I. Ramirez , J. R. Fish , D. L. Lambert , C. Allende Prieto

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

The Li enrichment in the Universe still presents various puzzles to astrophysics. One open issue is that of obtaining estimates for the rate of e-captures on 7Be, for T and rho conditions different from solar. This is important to model the…

Solar and Stellar Astrophysics · Physics 2015-06-12 Stefano Simonucci , Simone Taioli , Maurizio Busso , Sara Palmerini

The chemical evolution of lithium in the Milky Way represents a major problem in modern astrophysics. Indeed, lithium is, on the one hand, easily destroyed in stellar interiors, and, on the other hand, produced at some specific stellar…

Astrophysics of Galaxies · Physics 2016-10-26 G. Guiglion , P. de Laverny , A. Recio-Blanco , C. C. Worley , M. De Pascale , T. Masseron , N. Prantzos , S. Mikolaitis

The primordial abundances of light elements produced in the standard theory of Big Bang nucleosynthesis (BBN) depend only on the cosmic ratio of baryons to photons, a quantity inferred from observations of the microwave background. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-20 J. Christopher Howk , Nicolas Lehner , Brian D. Fields , Grant J. Mathews

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…

We present Li, Na, Al and Fe abundances of 199 lower red giant branch stars members of the stellar system Omega Centauri, using high-resolution spectra acquired with FLAMES at the Very Large Telescope. The A(Li) distribution is peaked at…

Solar and Stellar Astrophysics · Physics 2018-10-31 A. Mucciarelli , M. Salaris , L. Monaco , P. Bonifacio , X. Fu , S. Villanova

Most of the previous studies on beryllium abundances in metal-poor stars have taken different Galactic populations as a whole when investigating the production and evolution of Be. In this Letter, we report on the detection of systematic…

Solar and Stellar Astrophysics · Physics 2011-08-26 Kefeng Tan , Gang Zhao

Convergent lines of evidence suggest that globular clusters host multiple stellar populations. It appears that they experience at least two episodes of star formation whereby a fraction of first-generation stars contribute astrated ejecta…

Two aspects of the chemical evolution of 4He in the Galaxy are considered on the basis of a sample of disk planetary nebulae by the application of corrections due to the contamination of 4He from the progenitor stars. First, the He/H radial…

Astrophysics · Physics 2007-05-23 W. J. Maciel
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