$1\leftrightarrow 2$ Processes of a Sterile Neutrino Around Electroweak Scale in the Thermal Plasma

Abstract

In this paper, we will apply the Goldstone equivalence gauge to calculate the $1\leftrightarrow 2$ processes of a sterile neutrino in the thermal plasma below the standard model (SM) critical temperature $T_c\approx 160\text{ GeV}$. The sterile neutrino's mass is around the electroweak scale $50\text{ GeV}\le m_N\le 200\text{ GeV}$, and the acquired thermal averaged effective width ${\bar{\Gamma }}_{\text{tot}}$ is continuous around the cross-over. We will also apply our results to perform a preliminary calculation of the leptogenesis.

HTL vertex corrections (Eqn.~(A4)) have been included to acquire the gauge invariant results. Data had been updated