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We consider the effects of the injections of energetic photon and electron (or positron) on the big-bang nucleosynthesis. We study the photodissociation of light elements in the early Universe paying particular attention to the case that…

High Energy Physics - Phenomenology · Physics 2021-01-06 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Kai Murai , Hitoshi Murayama

The current status of big bang nucleosynthesis is summarized. Particular attention is paid to recent observations of He4 and Li7 and their systematic uncertainties. Be and B are also discussed in connection to recent Li7 observations and…

Astrophysics · Physics 2007-05-23 Keith A. Olive

Using the primordial helium abundance, an upper limit to the magnetic moments for Dirac neutrinos had been provided by imposing restrictions on the number of the additional helicity states. Considering non-thermal photons produced in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Motohiko Kusakabe , A. B. Balantekin , Toshitaka Kajino , Y. Pehlivan

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…

Lithium is one of the few elements produced during the Big Bang Nucleosynthesis in the early universe. Moreover, its fragility makes it useful as a proxy for stellar environmental conditions. As such, the lithium abundance in old systems is…

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 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

We calculate the effect of variation in the light-current quark mass, $m_q$, on standard big bang nucleosynthesis. A change in $m_q$ at during the era of nucleosynthesis affects nuclear reaction rates, and hence primordial abundances, via…

Nuclear Theory · Physics 2010-01-15 J. C. Berengut , V. F. Dmitriev , V. V. Flambaum

Recently we presented a simple method for determining the correlated uncertainties of the light element abundances expected from big bang nucleosynthesis, which avoids the need for lengthy Monte Carlo simulations. We now extend this…

High Energy Physics - Phenomenology · Physics 2008-11-26 E. Lisi , Subir Sarkar , F. L. Villante

Using the recent WMAP determination of the baryon-to-photon ratio, 10^{10} \eta = 6.14 to within a few percent, big bang nucleosynthesis (BBN) calculations can make relatively accurate predictions of the abundances of the light element…

Astrophysics · Physics 2009-09-15 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

The synthesis of Li6 during the epoch of Big Bang nucleosynthesis (BBN) due to residual annihilation of dark matter particles is considered. By comparing the predicted Li6 to observations of this isotope in low-metallicity stars, generic…

Astrophysics · Physics 2009-11-10 Karsten Jedamzik

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

Following a brief introduction to early Universe cosmology, the current of status of big bang nucleosynthesis is reviewed and the concordance between theory and observation is examined in detail. The abundances of He4 and Li7 determine the…

Astrophysics · Physics 2007-05-23 Keith A. Olive

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

We consider the effect of inhomogeneous neutrino degeneracy on Big Bang nucleosynthesis for the case where the distribution of neutrino chemical potentials is given by a Gaussian. The chemical potential fluctuations are taken to be…

Astrophysics · Physics 2009-11-07 Spencer D. Stirling , Robert J. Scherrer

We review the Cosmology and Physics underlying Primordial Nucleosynthesis and survey current observational data in order to compare the predictions of Big Bang Nucleosynthesis with the inferred primordial abundances. From this comparison we…

Astrophysics · Physics 2008-11-26 Keith A. Olive , Gary Steigman , Terry P. Walker

The comparison of cosmic abundances of the light elements with the density of baryonic stars and gas in the universe today provides a critical test of big bang theory and a powerful probe of the nature of dark matter. A new technique allows…

Astrophysics · Physics 2009-09-25 Craig J. Hogan

The last parameter of big-bang nucleosynthesis, the baryon density, is being pinned down by measurements of the deuterium abundance in high-redshift hydrogen clouds. When it is determined, it will fix the primeval light-element abundances.…

Astrophysics · Physics 2008-11-26 David N. Schramm , Michael S. Turner

We address the emerging discrepancy between the Big Bang Nucleosynthesis data and standard cosmology, which asks for a bit longer evolution time. If this effect is real, one possible implication (in a framework of brane cosmology model) is…

High Energy Physics - Theory · Physics 2009-08-18 V. V. Flambaum , E. V. Shuryak

Sasankan et al, have recently claimed that there are significant deviations in the phase-space distributions of the kinetic energies of nuclei from the Maxwell-Boltzmann form usually assumed in BBN, and further, that these deviations lead…

High Energy Physics - Phenomenology · Physics 2018-11-22 Samuel D. McDermott , Michael S. Turner