Energy spectrum of thermalizing high energy decay products in the early universe
Manuel Drees, Bardia Najjari
Abstract
Abstract We revisit the Boltzmann equation governing the spectrum of energetic particles originating from the decay of massive progenitors during the process of thermalization. We assume that these decays occur when the background temperature T is much less than the mass M of the progenitor. We pay special attention to the IR cutoff provided by the thermal bath, and include the suppression resulting from the interference of multiple scattering reactions (LPM effect). We solve the resulting integral equation numerically, and construct an accurate analytical fit of the solutions.
Topics & Concepts
PhysicsThermalisationCutoffThermalBoltzmann constantBoltzmann equationUniverseQuantum electrodynamicsQuantum mechanicsThermodynamicsCosmology and Gravitation TheoriesDark Matter and Cosmic PhenomenaParticle physics theoretical and experimental studies