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arXiv · 1811.05810

Decaying Dark Matter in Halos of Primordial Black Holes

Florian Kuhnel·Tommy Ohlsson
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Abstract

We investigate photon signatures of general decaying dark-matter particles in halos of primordial black holes. We derive the halo-profile density and the total decay rate for these combined dark-matter scenarios. For the case of axion-like particles of masses below $\mathcal{O}( 1 )\,$keV, we find strong bounds on the decay constant which are several orders of magnitude stronger than the strongest existing bounds, for all halo masses above $\mathcal{O}( 10^{-5} )$ solar masses. Using future X-ray measurements, it will be possible to push these bounds on such combined dark-matter scenarios even further.

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Florian Kuhnel, Tommy Ohlsson. 2018-11-14. Decaying Dark Matter in Halos of Primordial Black Holes. https://doi.org/10.1140/epjc%2Fs10052-019-7173-x

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