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Un-evolved, very metal-poor stars are the most important tracers of the cosmic abundance of lithium in the early universe. Combining the standard Big Bang nucleosynthesis model with Galactic production through cosmic ray spallation, these…

Solar and Stellar Astrophysics · Physics 2015-06-16 Karin Lind , Jorge Melendez , Martin Asplund , Remo Collet , Zazralt Magic

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

Big-bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. We briefly overview the essentials of this physics, and…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 Richard H. Cyburt , Brian D. Fields , Keith A. Olive , Tsung-Han Yeh

Big bang nucleosynthesis (BBN) and the cosmic baryon density from cosmic microwave background anisotropies together predict a primordial Li7 abundance a factor of 2--3 higher than that observed in galactic halo dwarf stars. A recent…

Astrophysics · Physics 2008-12-18 Brian D. Fields , Keith A. Olive , Elisabeth Vangioni-Flam

Assuming the best numerical value for the cosmic baryonic density and the existence of three neutrino flavors, standard big bang nucleosynthesis is a parameter-free model. It is important to assess if the observed primordial abundances can…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-07 Christian Iliadis , Alain Coc

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brian D. Fields , Paolo Molaro , Subir Sarkar

The $^6$Li abundance observed in metal poor halo stars appears to exhibit a plateau as a function of metallicity similar to that for $^7$Li, suggesting a big bang origin. However, the inferred primordial abundance of $^6$Li is $\sim$1000…

Standard Big Bang Nucleosynthesis at the baryon density determined by the microwave anisotropy spectrum predicts an excess of \li7 compared to observations by a factor of 4-5. In contrast, BBN predictions for D/H are somewhat below (but…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Keith A. Olive , Patrick Petitjean , Elisabeth Vangioni , Joseph Silk

Inhomogeneous big bang nucleosynthesis (BBN) produces a spatially inhomogeneous distribution of element abundances at $T \sim 10^9$ K, but subsequent element diffusion will tend to erase these inhomogeneities. We calculate the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2021-07-07 Robert J. Scherrer

To elucidate the significance of the effect of systematic uncertainties in light element abundance estimates on cosmological bounds derivable from Big Bang Nucleosynthesis (BBN) we present tables giving bounds on $\Omega_{baryon}$ and…

Astrophysics · Physics 2009-10-22 Lawrence M. Krauss , Peter J. Kernan

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial…

Astrophysics · Physics 2011-02-09 Brian Fields , Subir Sarkar

Primordial nucleosynthesis is one of the three historical evidences for the big bang model, together with the expansion of the universe and the cosmic microwave background. Now that the number of neutrino families and the baryonic densities…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-07 Cyril Pitrou , Alain Coc , Jean-Philippe Uzan , Elisabeth Vangioni

A key pillar of modern cosmology, Big Bang Nucleosynthesis (BBN) offers a probe of the particle content and expansion rate of the Universe a mere few minutes after the beginning. When compared with the BBN predictions, the observationally…

Astrophysics · Physics 2007-05-23 Gary Steigman

Recently, the first lithium detection outside of the Milky Way was made in low-metallicity gas of the Small Magellanic Cloud, which was at the level of the expected primordial value. Part of the observed lithium in any environment has…

High Energy Astrophysical Phenomena · Physics 2016-10-12 A. Ćiprijanović

Observational constraints on the primordial lithium abundance are important for the evaluation of the baryonic density of the universe. Its precise determination however suffers from uncertainties due to the possible depletion of this…

Astrophysics · Physics 2009-10-30 Sylvie Vauclair , Corinne Charbonnel

Observations of clusters and super clusters of galaxies have indicated that the Universe is more dominated by baryons than ever estimated in the homogeneous cosmological model for primordial nucleosynthesis. Recent detections of possibly…

Astrophysics · Physics 2009-10-30 T. KAJINO , M. ORITO

Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…

Astrophysics · Physics 2008-02-03 Craig J. Hogan

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) anisotropies independently predict the universal baryon density. Comparing their predictions will provide a fundamental test on cosmology. Using BBN and the CMB…

Astrophysics · Physics 2009-11-07 Richard H. Cyburt

Evolutionary trends in the surface abundances of heavier elements have recently been identified in the globular cluster NGC 6397 ([Fe/H]=-2), indicating the operation of atomic diffusion in these stars. Such trends constitute important…

Astrophysics · Physics 2009-11-13 K. Lind , A. J. Korn , P. S. Barklem , F. Grundahl

We present new upper and lower bounds to the primordial abundances of deuterium and helium-3 based on observational data from the solar system and the interstellar medium. Independent of any model for the primordial production of the…

Astrophysics · Physics 2009-10-22 N. Hata , R. J. Scherrer , G. Steigman , D. Thomas , T. P. Walker
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