Soft gamma-ray emission from plasma winds around evaporating primordial black holes

It is now accepted that within the Standard Model of particles the evaporat ing primordial black holes cannot produce the detectable gamma-ray bursts b ecause the expected photon flux from black-hole explosions is too weak, and consists mainly of GeV photons. Contrary to this verdict, we put forward a scenario, in which a large fraction of black-hole power is converted into the photon luminosity in the MeV spectral range, producing a burst of durat ion 10(-1) - 10(3) s. We show that some of the gamma-ray bursts detected by BATSE can be associated with evaporating black holes.