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Related papers: The lithium problem, a phenomenologist's perspecti…

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Two problems are discussed here. The first one is the 0.4 dex discrepancy between the 7Li abundance derived from the spectra of metal-poor halo stars on the one hand, and from Big Bang nucleosynthesis, based on the cosmological parameters…

The primordial Lithium Problem is intimately connected to the assumption that ${}^{7}{\rm Li}$ observed in metal-poor halo stars retains its primordial abundance, which lies significantly below the predictions of standard big-bang…

Astrophysics of Galaxies · Physics 2022-04-08 Brian D. Fields , Keith A. Olive

Why is the lithium abundance constant in the so-called lithium plateau while all predictions suggest that it should vary from star to star? Can we find a "lithium attractor" which would remain stable in halo stars while fundamental…

Astrophysics · Physics 2009-10-31 C. Charbonnel , S. Vauclair

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

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…

The cosmological {7Li problem consists in explaining why the primordial Li abundance, as predicted by the standard Big Bang nucleosynthesis theory with constraints from WMAP and Planck, is a factor of 3 larger than the Li abundance measured…

Astrophysics of Galaxies · Physics 2021-05-12 Francesca Matteucci , Marta Molero , David S. Aguado , Donatella Romano

The presence of the lithium-6 isotope in some metal-poor stars is a matter of surprise because of the high values observed. Non-standard models of Big Bang nucleosynthesis and pre-Galactic cosmic ray fusion and spallation have been proposed…

Solar and Stellar Astrophysics · Physics 2009-09-29 A. E. Garcia Perez , W. Aoki , S. Inoue , S. G. Ryan , T. K. Suzuki , M. Chiba

While theoretical computations of the lithium abundances in Pop II stars predict variations from star to star, the most recent observations confirm the existence of a "lithium plateau" with no abundance dispersion. This apparent paradox has…

Astrophysics · Physics 2007-05-23 Sylvie Vauclair

The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at about a factor of three below the abundance predicted by…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 G. J. Mathews , A. Kedia , N. Sasankan , M. Kusakabe , Y. Luo , T. Kajino , D. G. Yamazaki , T. Makki , M. El Eid

The lithium problem arises from the significant discrepancy between the primordial 7Li abundance as predicted by BBN theory and the WMAP baryon density, and the pre-Galactic lithium abundance inferred from observations of metal-poor…

Astrophysics · Physics 2009-10-16 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

Since the pioneering observations of Spite & Spite in 1982, the constant lithium abundance of metal-poor ([Fe/H]<-1.3) halo stars near the turnoff has been attributed a cosmological origin. Closer analysis revealed that the observed…

Astrophysics · Physics 2008-11-26 L. Piau , T. C. Beers , D. S. Balsara , T. Sivarani , J. W. Truran , J. W. Ferguson

We discuss the 6Li abundance evolution within a hierarchical model of Galaxy formation which correctly reproduces the [Fe/H] distribution of metal-poor halo stars. Contrary to previous findings, we find that neither the level…

Astrophysics · Physics 2011-11-10 Carmelo Evoli , Stefania Salvadori , Andrea Ferrara

The nuclei of the lithium isotopes are fragile, easily destroyed, so that, at variance with most of the other elements, they cannot be formed in stars through steady hydrostatic nucleosynthesis. The 7Li isotope is synthesized during…

Astrophysics of Galaxies · Physics 2015-05-18 Monique Spite , François Spite

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite…

Astrophysics · Physics 2009-11-11 Ann Merchant Boesgaard , Megan C. Novicki , Alex Stephens

We review three Li problems. First, the Li problem in the Sun, for which some previous studies have argued that it may be Li-poor compared to other Suns. Second, we discuss the Li problem in planet hosting stars, which are claimed to be…

Solar and Stellar Astrophysics · Physics 2010-11-22 J. Melendez , I. Ramirez , L. Casagrande , M. Asplund , B. Gustafsson , D. Yong , J. D. do Nascimento , M. Castro , M. Bazot

The presence of 6Li in the atmospheres of metal-poor halo stars is usually inferred from the detection of a subtle extra depression in the red wing of the 7Li doublet line at 670.8 nm. However, the intrinsic line asymmetry caused by…

Solar and Stellar Astrophysics · Physics 2012-06-12 M. Steffen , R. Cayrel , E. Caffau , P. Bonifacio , H. -G. Ludwig , M. Spite

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…

Astrophysics · Physics 2009-11-13 Ann Merchant Boesgaard , Alex Stephens , Constantine P. Deliyannis

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

Explaining the well established observation that the expansion rate of the universe is apparently accelerating is one of the defining scientific problems of our age. Within the standard model of cosmology, the repulsive 'dark energy'…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-20 Marco Regis , Chris Clarkson

The lithium plateau observed in halo stars has long appeared as a paradox in the general context of the lithium abundance behavior in stellar outer layers. First, the plateau is flat, second, the lithium abundance dispersion is extremely…

Astrophysics · Physics 2009-11-06 Sylvie Theado , Sylvie Vauclair
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