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Neutrino non-standard interactions (NSI) with electrons, predicted in many extended theoretical models of particle physics, are known to alter the picture of neutrino decoupling from the cosmic plasma. We update previous analyses of…

High Energy Physics - Phenomenology · Physics 2026-03-02 Stefano Gariazzo , Jaume Moncho , Sergio Pastor , Ofelia Pisanti

The neutron beta-decay lifetime plays an important role both in understanding weak interactions within the framework of the Standard Model and in theoretical predictions of the primordial abundance of 4He in Big Bang Nucleosynthesis. In…

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

Spectral distortions (SDs) of the cosmic microwave background (CMB) provide a powerful tool for studying particle physics. Here we compute the distortion signals from decaying particles that convert directly into photons at different epochs…

Cosmology and Nongalactic Astrophysics · Physics 2022-08-17 Boris Bolliet , Jens Chluba , Richard Battye

In this work, we investigate the viability of some cosmological models derived from generalized horizon entropies, using Big Bang Nucleosynthesis (BBN) constraints. By analyzing the deviations in the expansion rate, we derive bounds on the…

General Relativity and Quantum Cosmology · Physics 2026-04-22 Kajal Phukan , Rajdeep Mazumdar , Kalyan Malakar , Kalyan Bhuyan

The high densities in the early Universe provide a unique laboratory to constrain couplings between feebly interacting particles, such as dark matter and neutrinos. In this article, we study how Big Bang Nucleosynthesis can constrain models…

High Energy Physics - Phenomenology · Physics 2025-09-30 Toni Bertólez-Martínez , Justo López-Sarrión , Jordi Salvado

In big bang nucleosynthesis (BBN), the light matter abundance is dictated by the neutron-to-proton ($n/p$) ratio which is controlled by the standard weak processes in the early universe. Here, we study the effect of an extra particle…

High Energy Physics - Phenomenology · Physics 2024-06-24 Deep Ghosh

Gravitinos are a fundamental prediction of supergravity, their mass ($m_{G}$) is informative of the value of the SUSY breaking scale, and, if produced during reheating, their number density is a function of the reheating temperature…

High Energy Physics - Phenomenology · Physics 2018-07-11 Emanuela Dimastrogiovanni , Lawrence M. Krauss

The temperature and polarization anisotropies of the cosmic microwave background (CMB) have been used to set constraints on decaying dark matter models down to keV masses. In this work, we extend these limits down to the sub-keV mass range.…

Cosmology and Nongalactic Astrophysics · Physics 2024-08-27 Clara Xu , Wenzer Qin , Tracy R. Slatyer

Using the cosmological constants derived from WMAP, the standard big bang nucleosynthesis (SBBN) predicts the light elements primordial abundances for 4He, 3He, D, 6Li and 7Li. These predictions are in satisfactory agreement with the…

Cosmology and Nongalactic Astrophysics · Physics 2012-08-13 M. Spite , F. Spite , P. Bonifacio

We report on the status of primordial nucleosynthesis in light of recent results on CMB anisotropies from WMAP experiment. Theoretical estimates for nuclei abundances, along with the corresponding uncertainties, are evaluated using a new…

Astrophysics · Physics 2009-11-10 A. Cuoco , F. Iocco , G. Mangano , G. Miele , O. Pisanti , P. D. Serpico

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

In this paper we set bounds on the radiation content of the Universe and neutrino properties by using the WMAP-5 year CMB measurements complemented with most of the existing CMB and LSS data (WMAP5+All),imposing also self-consistent BBN…

Astrophysics · Physics 2009-06-23 L. A. Popa , A. Vasile

The lecture is devoted to the comparison of a few models of cosmic recombination kinetics with recent CMB anisotropy data and to corresponding predictions for the upcoming PLANCK mission. The influence of additional sources of ionized…

Astrophysics · Physics 2007-05-23 Pavel D. Naselsky

We observe that photon cooling after big bang nucleosynthesis (BBN) but before recombination can remove the conflict between the observed and theoretically predicted value of the primordial abundance of $^7$Li. Such cooling is ordinarily…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 O. Erken , P. Sikivie , H. Tam , Q. Yang

Many models of new physics including variants of supersymmetry predict metastable long-lived particles that can decay during or after primordial nucleosynthesis, releasing significant amounts of non-thermal energy. The hadronic energy…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-25 Maxim Pospelov , Josef Pradler

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

The effective number of neutrino species, $N_{\rm eff}$, serves as a key fitting parameter extensively employed in cosmological studies. In this work, we point out a fundamental inconsistency in the conventional treatment of $N_{\rm eff}$…

High Energy Physics - Phenomenology · Physics 2026-04-27 Sougata Ganguly , Tae Hyun Jung , Seokhoon Yun

The subject of cosmological hydrogen recombination has received much attention recently because of its importance to predictions for and cosmological constraints from CMB observations. While the central role of the two-photon decay 2s->1s…

Astrophysics · Physics 2008-11-26 Christopher M. Hirata

We study the finite temperature and density effects on beta decay rates to compute their contributions to nucleosynthesis in the early universe and compact stars. We express nucleosynthesis parameters as a function of temperature and…

High Energy Physics - Phenomenology · Physics 2014-03-24 Samina S Masood