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arXiv · 1307.2561

The cosmic-ray positron excess from a local Dark Matter over-density

A. Hektor·M. Raidal·A. Strumia·E. Tempel
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Abstract

We show that the cosmic-ray positron excess measured by PAMELA and AMS could be induced by Dark Matter annihilations in a local over-density. In such a context leptophilic DM is not needed and good fits to positron data, in agreement with antiproton and gamma-ray measurements, are obtained for DM annihilations to $WW$, $hh$, $ZZ$, $ t \bar t$, $b \bar b$, $q\bar q$ channels. The classic Dark Matter candidates, such as the pure supersymmetric Wino with standard thermal annihilation cross-section, can fit the positron excess, without invoking any additional assumption on Dark Matter properties.

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A. Hektor, M. Raidal, A. Strumia, E. Tempel. 2013-07-09. The cosmic-ray positron excess from a local Dark Matter over-density. https://doi.org/10.1016/j.physletb.2013.11.017

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