Spectral features of non-equilibrium antineutrinos of primordial nucleosynthesis

TL;DR

This paper calculates the spectra of non-equilibrium antineutrinos produced during primordial nucleosynthesis, considering Coulomb interactions, and explores how these spectra depend on the baryon-to-photon ratio, offering insights into early Universe processes.

Contribution

It provides detailed calculations of antineutrino spectra from primordial nucleosynthesis including Coulomb effects and analyzes their dependence on cosmological parameters.

Findings

Antineutrino spectra are significantly affected by Coulomb interactions.

Spectra depend on the baryon-to-photon ratio $ta$, linking observations to cosmological parameters.

Observing these antineutrinos can provide direct insights into early Universe conditions.

Abstract

During the era of primordial nucleosynthesis the background of non-equilibrium antineutrinos is being formed due to decays of neutrons and nuclei of tritium. The spectra of antineutrinos of this background were calculated taking into account the Coulomb interaction between electron and daughter nucleus in $\beta^-$-decay. The dependence of these spectra on the value of the baryon-to-photon ratio $\eta$ at the period of primordial nucleosynthesis is investigated. The observations of these antineutrinos will allow us to look directly at the very early Universe and nonequilibrium processes taken place before, during, and some time after primordial nucleosynthesis. In any case, this phenomenon is one more aspect in the picture of the standard cosmological model.