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Related papers: Primordial beryllium as a big bang calorimeter

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We investigate the non-radiative decay during nucleosynthesis of a massive tau neutrino with mass 0.1 - 1 MeV into an electron neutrino and a scalar or pseudoscalar particle, $\phi$. The full Boltzmann equation is used and shown to give…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Hannestad

We test different Big Bang Nucleosynthesis scenarios using the recent results on the Cosmic Microwave Background Anisotropies provided by the BOOMERanG and MAXIMA-1 experiments versus the observed abundances of 4He, D and 7Li. The…

Astrophysics · Physics 2009-10-31 S. Esposito , G. Mangano , A. Melchiorri , G. Miele , O. Pisanti

The observed cosmic abundances of light elements are most consistent with each other, and with the predictions of big bang nucleosynthesis,if, contrary to the usual assumption, galactic chemical evolution reduces $(D+\ ^3He)/H$ with time.…

Astrophysics · Physics 2009-10-22 Craig J. Hogan

According to the standard models of particle physics and cosmology, there should be a background of cosmic neutrinos in the present Universe, similar to the cosmic microwave photon background. The weakness of the weak interactions renders…

High Energy Physics - Phenomenology · Physics 2013-05-27 Gary Steigman

In Poulin and Serpico [Phys. Rev. Lett. 114, 091101 (2015)] we have recently argued that when the energy of a photon injected in the primordial plasma falls below the pair-production threshold, the universality of the non-thermal photon…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-01 Vivian Poulin , Pasquale Dario Serpico

The late-time entropy production by the massive particle decay induces the various cosmological effects in the early epoch and modify the standard scenario. We investigate the thermalization process of the neutrinos after the entropy…

Astrophysics · Physics 2016-08-30 M. Kawasaki , K. Kohri , Naoshi Sugiyama

Assuming the lightest neutralino forms dark matter, we study its residual annihilation after freeze-out at the early universe. If taking place after the big bang nucleosynthesis (BBN) the annihilation products, especially at the hadronic…

High Energy Physics - Phenomenology · Physics 2008-04-17 Xiao-Jun Bi

The light element abundances probe the baryon density of the universe within a few minutes of the Big Bang. Of these relics from the earliest universe, deuterium is the baryometer of choice. By comparing its primordial abundance inferred…

Astrophysics · Physics 2015-06-24 Gary Steigman

In the primordial Big Bang nucleosynthesis (BBN), only the lightest nuclides (D, $^3$He, $^4$He, and $^7$Li) were synthesized in appreciable quantities, and these relics provide us a unique window on the early universe. Currently, BBN…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-23 J. J. He , S. Q. Hou , A. Parikh , D. Kahl , C. A. Bertulani , other collaborators

In the standard picture of big-bang nucleosynthesis the yields of D, $^3$He, $^4$He, and $^7$Li only agree with their inferred primordial abundances if the fraction of critical density contributed by baryons is between $0.01h^{-2}$ and…

Astrophysics · Physics 2009-10-22 G. Gyuk , M. S. Turner

The success of primordial nucleosynthesis has been limited by the long-standing Lithium problem. We use a self-consistent perturbative analysis of the effects of relevant theoretical parameters on primordial nucleosynthesis, including…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-08 M. Deal , C. J. A. P. Martins

Big bang nucleosynthesis provides the earliest probe of standard model physics, at a time when the universe was less than a thousand seconds old. It determines the abundances of the lightest nuclides, which give rise to the subsequent…

Cosmology and Nongalactic Astrophysics · Physics 2020-05-27 Rafael S. de Souza , Tan Hong Kiat , Alain Coc , Christian Iliadis

$f(R)$ gravity is one of the serious alternatives of general relativity having a large range of astronomical consequences. In this work, we study Big Bang Nucleosynthesis (BBN) in $f(R)$ gravity theory. We consider modification to gravity…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-13 Abhijit Talukdar , Sanjeev Kalita

Oscillations between ordinary and sterile neutrinos can generate large neutrino asymmetries in the early universe. These asymmetries can significantly affect big bang nucleosynthesis (BBN) through modification of nuclear reaction rates. We…

High Energy Physics - Phenomenology · Physics 2011-07-19 N. F. Bell , R. Foot , R. R. Volkas

Oxygen is a much better evolutionary index than iron to follow the history of Lithium-Beryllium-Boron (LiBeB) since it is the main producer of these light elements at least in the early Galaxy. The O-Fe relation is crucial to the…

Astrophysics · Physics 2007-05-23 Elisabeth Vangioni-Flam , Michel Casse

We investigate how the resonant conversion at a temperature $\bar{T}=25$-$65$ keV of a fraction of the CMB photons into an axion-like majoron affects BBN. The scenario, that assumes the presence of a primordial magnetic field and the…

High Energy Physics - Phenomenology · Physics 2023-11-20 Antonio J. Cuesta , José I. Illana , Manuel Masip

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 R\'{e}nyi entropy, a one-parameter generalization of Boltzmann-Gibbs entropy, offers a promising framework for probing quantum gravitational effects in cosmology. By modifying the entropy-area relation of the apparent horizon, R\'{e}nyi…

General Physics · Physics 2025-07-22 Ahmad Sheykhi , Ava Shahbazi Sooraki

Effects of light millicharged dark matter particles on primordial nucleosynthesis are considered. It is shown that if the mass of such particles is much smaller than the electron mass, they lead to strong overproduction of Helium-4. An…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Zurab Berezhiani , Aleksander Dolgov , Igor Tkachev

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
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