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In the first thousand seconds of its evolution the Universe was a primordial nuclear reactor synthesizing the nuclides D, $^3$He, $^4$He and $^7$Li. These messengers from the Big Bang provide a unique window on the early, hot, dense…

Astrophysics · Physics 2009-10-28 Gary Steigman

Charged massive particles (CHAMPs), when present during the Big Bang nucleosynthesis (BBN) era, may significantly alter the synthesis of light elements when compared to a standard BBN scenario. This is due to the formation of bound states…

Astrophysics · Physics 2008-12-18 Karsten Jedamzik

We explore the effect of neutron lifetime and its uncertainty on standard big-bang nucleosynthesis (BBN). BBN describes the cosmic production of the light nuclides $^1{\rm H}$, ${\rm D}$, $^3{\rm H}$+$^3{\rm He}$, $^4{\rm He}$, and $^7{\rm…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields

We present an improved calculation of the light element abundances in the framework of Big Bang nucleosynthesis as a function of the Higgs vacuum expectation value $v$. We compare the methods of our calculation to previous literature…

High Energy Physics - Phenomenology · Physics 2024-06-18 Helen Meyer , Ulf-G. Meißner

We study effects of long-lived massive particles, which decay during the big-bang nucleosynthesis (BBN) epoch, on the primordial abundances of light elements. Compared to the previous studies, (i) the reaction rates of the standard BBN…

High Energy Physics - Phenomenology · Physics 2018-12-04 Masahiro Kawasaki , Kazunori Kohri , Takeo Moroi , Yoshitaro Takaesu

We consider the effect on Big Bang Nucleosynthesis (BBN) of new measurements of the $d(p,\gamma){}^3$He cross section by the LUNA Collaboration. These have an important effect on the primordial abundance of D/H which is also sensitive to…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-23 Tsung-Han Yeh , Keith A. Olive , Brian D. Fields

Big Bang Nucleosynthesis (BBN) has increasingly become the tool of choice for investigating the permitted variation of fundamental constants during the earliest epochs of the Universe. Here we present a BBN calculation that has been…

Nuclear Theory · Physics 2009-11-10 J. P. Kneller , G. C. McLaughlin

We update Standard Big Bang Nucleosynthesis (SBBN) calculations on the basis of recent nuclear physics compilations (NACRE in particular), experimental and theoretical works. By a Monte--Carlo technique, we calculate the uncertainties on…

Astrophysics · Physics 2009-11-07 Alain Coc , Elisabeth Vangioni-Flam , Michel Cass'e , Marc Rabiet

The primordial abundance of deuterium produced during Big Bang Nucleosynthesis (BBN) depends sensitively on the universal ratio of baryons to photons, an important cosmological parameter probed independently by the Cosmic Microwave…

Astrophysics of Galaxies · Physics 2015-05-13 Gary Steigman

We consider the effects of metastable charged sparticles on Big-Bang Nucleosynthesis (BBN), including bound-state reaction rates and chemical effects. We make a new analysis of the bound states of negatively-charged massive particles with…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Richard H. Cyburt , John Ellis , Brian D. Fields , Feng Luo , Keith A. Olive , Vassilis C. Spanos

This article presents an original code for Big Bang Nucleosynthesis in a baryon inhomogeneous model of the universe. In this code neutron diffusion between high and low baryon density regions is calculated simultaneously with the nuclear…

Astrophysics · Physics 2009-11-11 Juan F. Lara

We extend a recently developed Big Bang Nucleosynthesis (BBN) code, {\tt PRyMordial}, to constrain a broad class of Grand Unified Theories to which BBN is sensitive, since these lead to varying fundamental couplings. A previously developed…

High Energy Physics - Phenomenology · Physics 2026-04-07 I. M. Dreyer , C. J. A. P. Martins

The standard theory of electromagnetic cascades onto a photon background predicts a quasi-universal shape for the resulting non-thermal photon spectrum. This has been applied to very disparate fields, including non-thermal big bang…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Vivian Poulin , Pasquale D. Serpico

Observations of low-metallicity halo stars have revealed a puzzling result: the abundance of \li7 in these stars is at least three times lower than their predicted primordial abundance. It is unclear whether the cause of this disagreement…

Astrophysics of Galaxies · Physics 2015-06-12 Tijana Prodanovic , Tamara Bogdanovic , Dejan Urosevic

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

We investigate the observational constraints on the inhomogeneous big-bang nucleosynthesis that Matsuura et al. suggested the possibility of the heavy element production beyond ${}^7$Li in the early universe. From the observational…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-21 Riou Nakamura , Masa-aki Mashimoto , Shin-ichiro Fujimoto , Katsuhiko Sato

The primordial lithium abundance inferred from observations of metal-poor stars is ~3 times smaller than the theoretical value in standard big bang nucleosynthesis (BBN) model. We assume a simple model including a sterile neutrino nu_H with…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-29 Hiroyuki Ishida , Motohiko Kusakabe , Hiroshi Okada

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

Big Bang nucleosynthesis in the presence of decaying relic neutral particles is examined in detail. All non-thermal processes important for the determination of light-element abundance yields of 2H, 3H, 3He, 4He, 6Li, and 7Li are coupled to…

High Energy Physics - Phenomenology · Physics 2009-11-11 Karsten Jedamzik

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
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