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arXiv · 0906.3103

Visible and Dark Matter Genesis and Cosmic Positron/Electron Excesses

Pei-Hong Gu·Utpal Sarkar·Xinmin Zhang
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Abstract

Dark and baryonic matter contribute comparable energy density to the present Universe. The dark matter may also be responsible for the cosmic positron/electron excesses. We connect these phenomena with Dirac seesaw for neutrino masses. In our model (i) the dark matter relic density is a dark matter asymmetry generated simultaneously with the baryon asymmetry so that we can naturally understand the coincidence between the dark and baryonic matter; (ii) the dark matter mostly decays into the leptons so that its decay can interpret the anomalous cosmic rays with positron/electron excesses.

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Pei-Hong Gu, Utpal Sarkar, Xinmin Zhang. 2009-09-24. Visible and Dark Matter Genesis and Cosmic Positron/Electron Excesses. https://doi.org/10.1103/physrevd.80.076003

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