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The pre-Galactic abundance of lithium offers a unique window into non-thermal cosmological processes. The primordial Li abundance is guaranteed to be present and probes big bang nucleosynthesis (BBN), while an additional Li component is…

Astrophysics · Physics 2007-05-23 Tijana Prodanovic , Brian D. Fields

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…

Solar and Stellar Astrophysics · Physics 2025-08-28 Xuefeng Li , Jianrong Shi , Yan Li , Hongliang Yan , Jinghua Zhang

We investigate lithium depletion in standard stellar models (SSMs) and main sequence (MS) open clusters, and explore the origin of the Li dispersion in young, cool stars of equal mass, age and composition. We first demonstrate that SSMs…

Solar and Stellar Astrophysics · Physics 2015-06-18 Garrett Somers , Marc Pinsonneault

Lithium is one of the few primordially produced elements. The value of the primordial Li is taken to be that observed in metal--poor dwarfs, where it is not contaminated by stellar Li sources which act on longer time scales. The atmospheric…

Astrophysics · Physics 2009-10-30 Piercarlo Bonifacio , Paolo Molaro

In 1982, Monique and Francois Spite discovered that the 7Li abundance in the atmosphere of old metal-poor dwarf stars in the galactic halo was independent of metallicity and temperature. Since then, 7Li abundance in the Universe has become…

High Energy Astrophysical Phenomena · Physics 2014-02-24 Rachid Ouyed

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…

Solar and Stellar Astrophysics · Physics 2025-01-29 M. L. L. Dantas , R. Smiljanic , R. Boesso , H. Rocha-Pinto , L. Magrini , G. Guiglion , D. Romano

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…

Astrophysics · Physics 2009-11-10 Avi M. Mandell , Jian Ge , Norm Murray

Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements. Deuterium and 4He measurements agree well with expectations, but 7Li…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-19 Brian D. Fields

The depletion of lithium during the pre-main sequence and main sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. In the…

Astrophysics · Physics 2011-05-05 M. H. Pinsonneault , T. P. Walker , G. Steigman , V. K. Narayanan

We show that element diffusion can produce large fluctuations in the initial helium abundance of the star-forming clouds. Diffusion time-scale, which in stars is much larger than the Hubble time, can fall below 10^8 years in the neutral gas…

Astrophysics · Physics 2009-11-11 Leonid Chuzhoy

To constrain the universe before recombination (380000 years after the Big Bang), we mostly rely on the measurements of the primordial abundances that indicate the first insight into the thermal history of the universe. The first production…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-30 Tahani Makki , Mounib El Eid , Grant Mathews

Most of relatively warm, unevolved metal-poor stars ($T_{\rm eff}\gtrsim 5800\,\mathrm{K}$ and $[{\rm Fe/H}]\lesssim -1.5$) exhibit almost constant lithium abundances, irrespective of metallicity or effective temperature, and thus form the…

Solar and Stellar Astrophysics · Physics 2017-06-21 Tadafumi Matsuno , Wako Aoki , Takuma Suda , Haining Li

In this review I briefly discuss the theory of pre-main-sequence (PMS) Li depletion in low-mass (0.075<M<1.2 Msun) stars and highlight those uncertain parameters which lead to substantial differences in model predictions. I then summarise…

Astrophysics · Physics 2015-12-09 R. D. Jeffries

We present Li and Fe abundances for 87 stars in the GC M4,obtained with GIRAFFE high-resolution spectra. The targets range from the TO up to the RGB Bump. The Li abundance in the TO stars is uniform, with an average value A(Li)=2.30+-0.02…

Solar and Stellar Astrophysics · Physics 2015-05-20 A. Mucciarelli , M. Salaris , L. Lovisi , F. R. Ferraro , L. Lanzoni , S. Lucatello , R. G. Gratton

Recent abundance measurements in damped Lyman-alpha galaxies, supplemented with unpublished Keck observations, are discussed. The metallicity distribution with cosmic time is examined for clues about the degree of enrichment, the onset of…

Astrophysics · Physics 2007-05-23 Limin Lu , Wallace L. W. Sargent , Thomas A. Barlow

Very high-quality spectra of 24 metal-poor halo dwarfs and subgiants have been acquired with ESO's VLT/UVES for the purpose of determining Li isotopic abundances. The derived 1D, non-LTE 7Li abundances from the LiI 670.8nm line reveal a…

We present an extensive study of lithium abundances in dwarf components of chromospherically active binary stars (CABS). Since most of these binaries have known radii, masses and ages, this kind of data is especially useful for comparisons…

We make use of high resolution, high signal-to-noise ratio spectra of 12 turn-off stars in the metal-poor globular cluster NGC 6397 to measure its lithium content. We conclude that they all have the same lithium abundance A(Li) = 2.34 with…

This paper presents the chemical abundance analysis of 217 stars in the metal-poor globular cluster NGC 6752, distributed from the turn-off to the lower red giant branch. Aluminium and Lithium abundances were derived through spectral…

Solar and Stellar Astrophysics · Physics 2022-02-09 J. Schiappacasse-Ulloa , S. Lucatello , M. J. Rain , A. Pietrinferni

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