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Related papers: Nuclear Reaction Rates and Primordial $^6$Li

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We present a new astrophysical site of the big bang nucleosynthesis (BBN) that are very peculiar compared with the standard BBN. Some models of the baryogenesis suggest that very high baryon density regions were formed in the early…

Astrophysics · Physics 2009-11-13 S. Matsuura , S. Fujimoto , S. Nishimura , M. Hashimoto , K. Sato

The cosmological abundance of nucleons determined from considerations of Big Bang nucleosynthesis allegedly provides compelling evidence for non-nucleonic dark matter. Recent developments in measurements of primordial light element…

Astrophysics · Physics 2007-05-23 Subir Sarkar

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

Residual late-time dark matter particle annihilations during and after Big Bang Nucleosynthesis (BBN) may alter the predicted cosmological abundances of the light elements. Within the constrained minimal supersymmetric extension of the…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

We investigate the effect on the Big Bang Nucleosynthesis (BBN) from the presence of a stochastic primordial magnetic field (PMF) whose strength is spatially inhomogeneous. We assume a uniform total energy density and a gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Yudong Luo , Toshitaka Kajino , Motohiko Kusakabe , Grant J. Mathews

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

Big Bang Nucleosynthesis (BBN) is studied within the framework of a two-parameter family of tensor-scalar theories of gravitation, with nonlinear scalar-matter coupling function a(phi). We run a BBN code modified by tensor-scalar gravity,…

Astrophysics · Physics 2009-10-30 Thibault Damour , Bernard Pichon

One of the still viable candidates for the dark matter is the so-called mirror matter. Its cosmological and astrophysical implications were widely studied in many aspects, pointing out the importance to go further with research and refine…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-14 Paolo Ciarcelluti

I consider the synthesis of 6Li due to the decay of relic particles, such as gravitinos or moduli, after the epoch of Big Bang Nucleosynthesis. The synthesized 6Li/H ratio may be compared to 6Li/H in metal-poor stars which, in the absence…

Astrophysics · Physics 2009-10-31 K. Jedamzik

There may be non-thermal cosmic rays during big-bang nucleosynthesis (BBN) epoch (dubbed as BBNCRs). This paper investigated whether such BBNCRs can be the origin of Lithium problem or not. It can be expected that BBNCRs flux will be small…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Ming-ming Kang , Yang Hu , Hong-bo Hu , Shou-hua Zhu

We calculate primordial abundances of light elements produced during big bang nucleosynthesis when the fine structure constant and/or the cosmic expansion rate take non-standard values. We compare them with the recent values of observed D,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kazuhide Ichikawa , Masahiro Kawasaki

We study the big-bang nucleosynthesis (BBN) scenario with late-decaying exotic particles with lifetime longer than $\sim 1$ sec. With a late-decaying particle in the early universe, predictions of the standard BBN scenario can be…

Astrophysics · Physics 2010-04-05 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi

An accurate quantum three-body calculation is performed for the new type of big-bang nucleosynthesis (BBN) reactions that are catalyzed by a long-lived negatively-charged, massive leptonic particle (called X^-) such as the supersymmetric…

Nuclear Theory · Physics 2009-08-11 Masayasu Kamimura , Yasushi Kino , Emiko Hiyama

The simplest, `standard' model of Big Bang Nucleosynthesis (SBBN) assumes three light neutrinos (N_nu = 3) and no significant electron neutrino asymmetry, leaving only one adjustable parameter: the baryon to photon ratio eta. The primordial…

Astrophysics · Physics 2009-11-10 James P. Kneller , Gary Steigman

The relic abundances of the light elements synthesized during the first few minutes of the evolution of the Universe provide unique probes of cosmology and the building blocks for stellar and galactic chemical evolution, while also enabling…

Astrophysics · Physics 2015-06-24 Gary Steigman

Big bang nucleosynthesis has long provided the primary determination of the cosmic baryon density $\omb h^2$, or equivalently the baryon-to-photon ratio, \eta. Recently, data on CMB anisotropies have become increasingly sensitive to \eta.…

Astrophysics · Physics 2008-11-26 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

We put bounds on the variation of the value of the fine structure constant $\alpha$, at the time of Big Bang nucleosynthesis. We study carefully all light elements up to $^7$Li. We correct a previous upper limit on $|\Delta \alpha /…

Astrophysics · Physics 2009-10-31 L. Bergstrom , S. Iguri , H. Rubinstein

Big Bang nucleosynthesis (BBN) theory predicts the abundances of the light elements D, $^3$He, $^4$He and $^7$Li produced in the early universe. The primordial abundances of D and $^4$He inferred from observational data are in good…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-17 S. Q. Hou , J. J. He , A. Parikh , D. Kahl , C. A. Bertulani , T. Kajino , G. J. Mathews , G. Zhao

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

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