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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

We assess the status of big-bang nucleosynthesis (BBN) in light of the final Planck data release and other recent developments, and in anticipation of future measurements. Planck data fix the cosmic baryon density to 0.9% precision, and…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-17 Brian D. Fields , Keith A. Olive , Tsung-Han Yeh , Charles Young

The ability to now make measurements of Be and B as well as put constraints on \lisix\ abundances in metal-poor stars has led to a detailed reexamination of Big Bang Nucleosynthesis in the $A\groughly6$ regime. The nuclear reaction network…

Astrophysics · Physics 2009-09-15 David Thomas , David N. Schramm , Keith A. Olive , Brian D. Fields

Big-bang nucleosynthesis is one of the cornerstones of the standard cosmology. For almost thirty years its predictions have been used to test the big-bang model to within a fraction of a second of the bang. The concordance that exists…

Astrophysics · Physics 2009-10-22 Craig J Copi , David N. Schramm , Michael S. Turner

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides -…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Michael Foley , Nishanth Sasankan , Motohiko Kusakabe , Grant. J. Mathews

The WMAP satellite, devoted to the observations of the anisotropies of the Cosmic Microwave Background (CMB) radiation, has recently provided a determination of the baryonic density of the Universe with unprecedented precision. Using this,…

We consider next-to-minimal supersymmetric standard model (NMSSM) which has a gauge singlet superfield. In the scale invariant superpotential we do not have the mass terms and the whole Lagrangian has an additional $Z_3$ symmetry. This…

High Energy Physics - Phenomenology · Physics 2016-07-12 Priyotosh Bandyopadhyay , Katri Huitu , Saurabh Niyogi

The `lithium problem' in Big Bang Nucleosynthesis (BBN) has recently focused on the reactions involving $^7$Be. The $^6$Li($p, \gamma$)$^7$Be reaction can provide us not only the information for destroying $^6$Li but also the information…

Nuclear Experiment · Physics 2018-03-30 Zhi-Hong Li , Er-Tao Li , Jun Su , Yun-Ju Li , You-Bao Wang , Sheng-Quan Yan , Bing Guo , Ding Nan , Wei-Ping Liu

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

The current status of big bang nucleosynthesis is reviewed. Particular attention is given to the degree at which the theory is consistent with the observation of the light element abundances.

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

Precise studies on the Galactic bulge, halo, thick disk, and globular clusters require stellar models with alpha enhancement and various He contents. For this purpose we complement existing PARSEC (PAdova-TRieste Stellar Evolution Code)…

Solar and Stellar Astrophysics · Physics 2017-02-10 Xiaoting Fu

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…

It has been demonstrated that Li-7 can be created in low mass red giant stars, via the Cameron-Fowler mechanism, due to extra deep mixing and the associated "cool bottom processing" (CBP). Under certain conditions, this Li-7 creation can…

Astrophysics · Physics 2008-02-03 I. -Juliana Sackmann , Arnold I. Boothroyd

Big Bang Nucleosynthesis is the theory of the production of the the light element isotopes of D, He3, He4, and Li7. After a brief review of the essential elements of the standard Big Bang model at a temperature of about 1 MeV, the…

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

The impact of unstable Majorana tau neutrinos on primordial nucleosynthesis is considered. The mass and lifetime of nu_tau are taken in the intervals 0.1-20 MeV and 0.001-400 sec respectively. The studied decay modes are nu_tau -> nu_mu +…

High Energy Physics - Phenomenology · Physics 2009-09-25 A. D. Dolgov , S. H. Hansen , S. Pastor , D. V. Semikoz

A discrepancy has emerged between the cosmic lithium abundance inferred by the WMAP satellite measurement coupled with the prediction of the standard big-bang nucleosynthesis theory, and the constant Li abundance measured in metal-poor halo…

Astrophysics of Galaxies · Physics 2015-05-19 L. Monaco , P. Bonifacio , L. Sbordone , S. Villanova , E. Pancino

We have investigated the constrained minimal supersymmetric standard model with three right-handed Majorana neutrinos whether there still is a parameter region which is consistent with all existing experimental data/limits such as…

High Energy Physics - Phenomenology · Physics 2018-06-13 Munehiro Kubo , Joe Sato , Takashi Shimomura , Yasutaka Takanishi , Masato Yamanaka

The cosmological lithium problem, that is, the discrepancy between the lithium abundance predicted by the Big Bang nucleosynthesis and the one observed for the stars of the 'Spite plateau', is one of the long standing problems of modern…

Solar and Stellar Astrophysics · Physics 2020-07-01 E. Tognelli , P. G. Prada Moroni , S. Degl'Innocenti , M. Salaris , S. Cassisi

We consider the effects on big bang nucleosynthesis (BBN) of the radiative decay of a long-lived massive particle. If high-energy photons are emitted after the BBN epoch ($t \sim 1 - 10^3$ sec), they may change the abundances of the light…

High Energy Physics - Phenomenology · Physics 2011-05-05 M. Kawasaki , K. Kohri , Takeo Moroi

We extend the model-independent likelihood analysis of big bang nucleosynthesis (BBN) based on He4 and Li7 to allow for numbers of degrees of freedom which differ from the standard model value characterized by $N_\nu = 3$. We use the…

High Energy Physics - Phenomenology · Physics 2008-11-26 Keith A. Olive , David Thomas
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