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arXiv · 1403.1212

Decaying Dark Atom constituents and cosmic positron excess

Konstantin Belotsky·Maxim Khlopov·Chris Kouvaris·Maxim Laletin
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Abstract

We present a scenario where dark matter is in the form of dark atoms that can accomodate the experimentally observed excess of positrons in PAMELA and AMS-02 while being compatible with the constraints imposed on the gamma-ray flux from Fermi/LAT. This scenario assumes that the dominant component of dark matter is in the form of a bound state between a helium nucleus and a $-2$ particle and a small component is in the form of a WIMP-like dark atom compatible with direct searches in underground detectors. One of the constituents of this WIMP-like state is a $+2$ metastable particle with a mass of 1 TeV or slightly below that by decaying to $e^+e^+$, $μ^+ μ^+$ and $τ^+ τ^+$ produces the observed positron excess. These decays can naturally take place via GUT interactions. If it exists, such a metastable particle can be found in the next run of LHC. The model predicts also the ratio of leptons over baryons in the Universe to be close to -3.

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Konstantin Belotsky, Maxim Khlopov, Chris Kouvaris, Maxim Laletin. 2014-03-05. Decaying Dark Atom constituents and cosmic positron excess. https://doi.org/10.1155/2014%2F214258

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