2009/04/30 by Wanlei Guo, Wan-Lei Guo, Xin Zhang
Physics and Astronomy · #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Particle physics theoretical and experimental studies #astro-ph.CO #gr-qc #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.79.115023
published as Phys.Rev.D79:115023,2009 · 5 pages, 2 figures. Comments and references added, publication in Phys. Rev. D
openalex publication_date 2009/06/26 · arxiv created 2009/07/02 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We investigate the dark matter annihilation in the brane-world and quintessence scenarios, in which the modified cosmological expansion rate can enhance the thermal relic density of dark matter. According to the observed dark matter abundance, we constrain the thermally averaged annihilation cross section ⟨\ensuremathσv⟩ in these two scenarios. In addition, the big bang nucleosynthesis and the partial-wave unitarity are also used to place bounds on ⟨\ensuremathσv⟩. It is found that both scenarios can lead to a large annihilation cross section, so they can be used to explain the recent PAMELA, ATIC, and PPB-BETS anomalies.