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Dark Matter Annihilation and the PAMELA, FERMI and ATIC Anomalies

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 نشر من قبل Hiroshi Okada
 تاريخ النشر 2009
  مجال البحث فيزياء
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If dark matter (DM) annihilation accounts for the tantalizing excess of cosmic ray electron/positrons, as reported by the PAMELA, ATIC, HESS and FERMI observatories, then the implied annihilation cross section must be relatively large. This results, in the context of standard cosmological models, in very small relic DM abundances that are incompatible with astrophysical observations. We explore possible resolutions to this apparent conflict in terms of non-standard cosmological scenarios; plausibly allowing for large cross sections, while maintaining relic abundances in accord with current observations.



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