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arXiv · 1009.1947

Primordial Black Hole as a Source of the Boost Factor

Ryo Saito·Satoshi Shirai
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Abstract

Primordial black holes (PBHs) accumulate weakly interacting massive particles (WIMPs) around them and form ultracompact minihalos (UCMHs), if the WIMP is a dominant component of the dark matter (DM). In this paper, we discuss that the UCMHs seeded by the PBHs with sub-earth mass enhance the WIMP annihilation in the present Universe and can successfully explain the positron and/or electron excess in cosmic ray observed by PAMELA/Fermi experiments. The signal is very similar to that from a decaying dark matter, which can explain the PAMELA and/or Fermi anomaly without conflict with any constraints as long as the decay mode is proper. In this scenario, the boost factor can be as large as 10^5. In addition, we discuss testability of our scenario by gamma-ray point source and gravitational-wave experiments.

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Ryo Saito, Satoshi Shirai. 2010-09-10. Primordial Black Hole as a Source of the Boost Factor. https://doi.org/10.1016/j.physletb.2011.01.038

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