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Related papers: Limits from BBN on Light Electromagnetic Decays

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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

Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…

Astrophysics · Physics 2009-06-23 Gary Steigman

We reanalyze the effect of magnetic fields in BBN, incorporating several features which were omitted in previous analyses. We find that the effects of coherent magnetic fields on the weak interaction rates and the electron thermodynamic…

Astrophysics · Physics 2014-10-13 Peter. J. Kernan , Glenn D. Starkman , Tammay Vachaspati

We report the results on Big Bang Nucleosynthesis (BBN) based on an updated code, with accuracy of the order of 0.1% on He4 abundance, compared with the predictions of other recent similar analysis. We discuss the compatibility of the…

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

The cosmic energy density in the form of radiation before and during Big Bang Nucleosynthesis (BBN) is typically parameterized in terms of the effective number of neutrinos N_eff. This quantity, in case of no extra degrees of freedom,…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 G. Mangano , G. Miele , S. Pastor , O. Pisanti , S. Sarikas

During Big Bang Nucleosynthesis (BBN), in the first 20 minutes of the evolution of the Universe, the light nuclides, D, 3He, 4He, and 7Li were synthesized in astrophysically interesting abundances. The Cosmic Microwave Background Radiation…

Astrophysics · Physics 2008-07-21 Gary Steigman

Primordial black holes (PBHs) with masses below $10^9\,\rm{g}$ are typically assumed to have negligible cosmological impact due to their rapid evaporation via Hawking radiation. However, the 'memory burden' effect, which is a quantum…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-30 Arnab Chaudhuri , Kazunori Kohri , Valentin Thoss

Big bang nucleosynthesis (BBN), an epoch of primordial nuclear transformations in the expanding Universe, has left an observable imprint in the abundances of light elements. Precision observations of such abundances, combined with…

High Energy Physics - Phenomenology · Physics 2011-04-14 Maxim Pospelov , Josef Pradler

We propose a correction of the standard Big Bang nucleosynthesis (BBN) scenario to resolve the primordial lithium problem by considering a possibility that the primordial plasma can deviate from the ideal state. In the standard BBN, the…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-16 Dukjae Jang , Youngshin Kwon , Kyujin Kwak , Myung-Ki Cheoun

We provide a new bound on the amplitude of primordial magnetic fields (PMFs) by using a novel mechanism, named {\it magnetic reheating}. Before the epoch of recombination, PMFs induce the fluid motions in a photon-baryon plasma through the…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-18 Shohei Saga , Hiroyuki Tashiro , Shuichiro Yokoyama

We study the impact of an early dark energy component (EDE) present during big bang nucleosynthesis (BBN) on the elemental abundances of deuterium D/H, and helium $Y_p$, as well as the effective relativistic degrees of freedom $N_{\rm…

High Energy Physics - Phenomenology · Physics 2024-11-18 David McKeen , Afif Omar

Big Bang Nucleosynthesis (BBN), the process of creation of lightest elements in the early universe, is a highly robust, precise, and ultimately successful theory that forms one of the three pillars of the standard hot-Big-Bang cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-12 Aidan Meador-Woodruff , Dragan Huterer

Scalar dark matter can interact with Standard Model (SM) particles, altering the fundamental constants of Nature in the process. Changes in the fundamental constants during and prior to Big Bang nucleosynthesis (BBN) produce changes in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-14 Y. V. Stadnik , V. V. Flambaum

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 investigate the scenario in which primordial black holes (PBHs) with masses Mpbh < 10^9 g undergo Hawking evaporation, around the Big-Bang nucleosynthesis (BBN) epoch. The evaporation process modifies the Universe's expansion rate and…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-06 Andrea Boccia , Fabio Iocco , Luca Visinelli

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

Possible influence of primordial black hole (PBH) evaporations on cosmic microwave background (CMB) is investigated. The spectrum distortions of CMB from the black-body spectrum are described by the chemical potential $\mu$ and the Compton…

Astrophysics · Physics 2008-11-26 Hiroyuki Tashiro , Naoshi Sugiyama

Big Bang Nucleosynthesis (BBN) is an important stage of a homogeneous and isotropic expanding universe. The results of calculation of the synthesis of light elements during this epoch can then be compared with the abundances of the light…

Nuclear Theory · Physics 2023-03-15 Chen Wu

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

Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…

Astrophysics · Physics 2009-11-11 Gary Steigman
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