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Searching for Primordial Black Holes in the Radio and X-Ray Sky
Daniele Gaggero1, Gianfranco Bertone1, Francesca Calore1,2
1GRAPPA, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands.
Abstract:
We model the accretion of gas onto a population of massive primordial black holes in the Milky Way and compare the predicted radio and x-ray emission with observational data. We show that, under conservative assumptions on the accretion process, the possibility that O(10)M_{⊙} primordial black holes can account for all of the dark matter in the Milky Way is excluded at 5σ by a comparison with a Very Large Array radio catalog at 1.4 GHz and at ≃40σ by a comparison with a Chandra x-ray catalog (0.5-8 keV). We argue that this method can be used to identify such a population of primordial black holes with more sensitive future radio and x-ray surveys.
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