2021/05/31 by Manuel Drees, Bardia Najjari
Physics and Astronomy · #Boltzmann constant #Boltzmann equation #Cosmology and Gravitation Theories #Cutoff #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #Physics #Quantum electrodynamics #Quantum mechanics #Thermal #Thermalisation #Thermodynamics #Universe #astro-ph.CO #hep-ph
paper · pdf · doi:10.1088/1475-7516/2021/10/009
published as JCAP 10 (2021) 009 · Including subsection 3.3 -- Published Journal Version
openalex publication_date 2021/10/01 · arxiv created 2022/03/21 · arxiv updated 2022/03/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
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.