http://arxiv.org/abs/1710.09458
We present several scenarios how capture of primordial black holes (PBHs) with masses $10^{-16} M_{\odot} \lesssim M_{\rm PBH} \lesssim 10^{-7} M_{\odot}$ by compact objects (white dwarfs or neutron stars) can source short gamma-ray bursts (sGRBs) as well as microquasars (MQs). A small PBH captured by a compact star will eventually consume the host, turning it into a stellar-mass BH. We argue that formation of an accretion disk around the resulting BH, which is an important prerequisite for standard sGRB production mechanisms, can be generic. The PBH-induced relativistic sGRB flares as well as continuous MQ jets will accelerate positrons to high energies. We find that if PBHs constitute a few percent or more of the dark matter, the generated positrons can address the excess observed in the positron flux by the Pamela, the AMS-02 and the Fermi-LAT experiments. The allowed resulting parameter space for primordial black holes to constitute dark matter is in a favorable region to permit for resolution of several other astronomical puzzles.
V. Takhistov
Fri, 27 Oct 17
21/60
Comments: 7 pages + 1 page supplement, 2 figures