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arXiv · 0812.0072

Breit-Wigner Enhancement of Dark Matter Annihilation

Masahiro Ibe·Hitoshi Murayama·T. T. Yanagida
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Abstract

We point out that annihilation of dark matter in the galactic halo can be enhanced relative to that in the early universe due to a Breit-Wigner tail, if the dark matter annihilates through a pole just below the threshold. This provides a new explanation to the "boost factor" which is suggested by the recent data of the PAMELA, ATIC and PPB-BETS cosmic-ray experiments.

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Masahiro Ibe, Hitoshi Murayama, T. T. Yanagida. 2008-11-29. Breit-Wigner Enhancement of Dark Matter Annihilation. https://doi.org/10.1103/physrevd.79.095009

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