2022/09/15 by Prolay Chanda, Jakub Scholtz, Chanda, Prolay +3 · 3 citations
Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #Dark Matter and Cosmic Phenomena #FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph)
paper · pdf · doi:10.48550/arxiv.2209.07541
openalex publication_date 2022/09/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/04
Cosmology may give rise to appreciable populations of both particle dark matter and primordial black holes (PBH) with the combined mass density providing the observationally inferred value Ω\rm DM≈0.26. However, previous studies have highlighted that scenarios with both particle dark matter and PBH are strongly excluded by γ-ray limits for particle dark matter with a velocity independent thermal cross section ⟨σv⟩∼3×10-26\rm cm3/\rm s, as is the case for classic WIMP dark matter. Here we extend these existing studies on s-wave annihilating particle dark matter to ascertain the limits from diffuse γ-rays on velocity dependent annihilations which are p-wave with ⟨σv ⟩∝ v2 or d-wave with ⟨σv ⟩∝ v4, which we find to be considerably less constraining. Furthermore, we highlight that even if the freeze-out process is p-wave it is relatively common for (loop/phase-space) suppressed s-wave processes to actually provide the leading contributions to the experimentally constrained γ-ray flux from the PBH halo. This work also utilyses a refined treatment of the PBH dark matter density profile and outlines an improved application of extra-galactic γ-ray bounds.