The impact of excited neutrinos on $\nu \bar{\nu}\to \gamma\gamma$ process

TL;DR

This paper investigates how excited neutrinos influence the neutrino-antineutrino annihilation into photons, showing they can lower the decoupling temperature significantly compared to the Standard Model predictions.

Contribution

It introduces the effect of excited neutrinos on the neutrino-photon decoupling temperature, a novel aspect not previously explored.

Findings

Excited neutrinos can significantly reduce the neutrino-photon decoupling temperature.

The impact of excited neutrinos alters the standard cosmological predictions.

Photon-neutrino decoupling can occur at lower temperatures due to excited neutrinos.

Abstract

We examine the effect of excited neutrinos on the annihilation of relic neutrinos with ultra high energy cosmic neutrinos for the $\nu \bar{\nu}\to \gamma\gamma$ process. The contribution of the excited neutrinos to the neutrino-photon decoupling temperature are calculated. We see that photon-neutrino decoupling temperature can be significantly reduced below the obtained value of the Standard Model with the impact of excited neutrinos.