Primordial Black Hole Binaries as a Source of Gamma-Ray Bursts and of a High-Frequent Gravitational Radiation

Abstract

Ultracompact primordial black hole binaries with masses > 10^{16} g are considered. If PBHB's contribute significant part of the dark matter of the Galaxy one can expect an existence of high-frequent non-thermal diffuse gravitational radiation with flux of ~1 erg cm^{-2} s^{-1}. The possibility of coalescence of the PBHB's in Galaxy's halo to be a source at least of a part of gamma-ray bursts (GRB) observed is discussed. The energy flux of gravitational radiation from those GRB's should exceed the energy flux of gamma-radiation by 7-8 orders of magnitude. The possibility of observation of PBHB through detection of the gravitational radiation burst coincident with GRB is emphasized. The PBHB also can be observed detecting a stationary gravitatonal radiation in the frequency range > 10^4 Hz and observing a high-frequent pulsation of a source's brightness in microlensing effects in the Galaxy's halo.