Thermal masses in leptogenesis

TL;DR

This paper examines the use of thermal masses in leptogenesis decay calculations, finding it a reasonable approximation with some quantum statistical corrections affecting accuracy.

Contribution

It assesses the validity of thermal mass approximations in leptogenesis, highlighting necessary corrections from quantum statistics and quasiparticle effects.

Findings

Thermal masses are a reasonable approximation for decay kinematics.

Quantum statistical effects introduce notable corrections.

Leptonic quasiparticles impact decay rate calculations.

Abstract

We investigate the validity of using thermal masses in the kinematics of final states in the decay rate of heavy neutrinos in leptogenesis calculations. We find that using thermal masses this way is a reasonable approximation, but corrections arise through quantum statistical distribution functions and leptonic quasiparticles.