Pair production near accreting black holes Academic Article uri icon


  • The non-relativistic temperature of the hard X-ray continuum in the spectrum of the black hole candidate 1E 1740.7-2942 during its hard state cannot be understood in terms of the conventional photon-photon pair production scenario's. The high pair creation rate during this state is indicated by the presence of a broad e-e+ annihilation line-like feature and needs the presence of a high temperature radiation field. We put forward a scenario in which the observed spectrum originates from the inner region of an accretion disk around a rapidly rotating black hole. For a not too high inclination angle, the gravitational redshift lowers the high local radiation temperature to the observed value. This mechanism necessitates a region of extremely strong gravity and is therefore unique for black holes. The presence of an annihilation line together with a low temperature X-ray continuum could therefore be considered as a black hole signature. ©1997. Published by Elsevier Science Ltd on behalf of COSPAR. All rights reserved.

author list (cited authors)

  • Belyanin, A. A., & van Oss, R. F

complete list of authors

  • Belyanin, AA||van Oss, RF

publication date

  • January 1, 1997 11:11 AM