2008/10/31 by Marc Kamionkowski, Stefano Profumo · 71 citations
Physics and Astronomy · #Annihilation #Astrophysics #Atomic physics #Cosmology and Gravitation Theories #Cross section (physics) #Dark Matter and Cosmic Phenomena #Dark matter #Galactic halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Intergalactic travel #Ionization #Nuclear physics #Particle (ecology) #Particle physics #Physics #Quantum mechanics #Radiation #Redshift #astro-ph #hep-ph
paper · pdf · doi:10.1103/physrevlett.101.261301
published in Physical Review Letters 101(26), 261301 (American Physical Society) · 11 pages, no figures; references and comments added
arxiv created 2008/11/06 · openalex publication_date 2008/12/29 · arxiv updated 2010/04/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Recent studies have considered modifications to the standard weakly interacting massive particle scenario in which the pair annihilation cross section (times relative velocity v) is enhanced by a factor 1/upsilon to approximately 10(-3) in the Galaxy, enough to explain several puzzling Galactic radiation signals. We show that in these scenarios a burst of weakly interacting massive particle annihilation occurs in the first collapsed dark-matter halos. We show that severe constraints to the annihilation cross section derive from measurements of the diffuse extragalactic radiation and from ionization and heating of the intergalactic medium.