Gamma-Ray Bursts from Radio-Quiet Quasars
  We study positional coincidences between gamma-ray bursts in the BATSE 3B catalogue and quasars/AGN taken from the Veron-Cetty & Veron compilation. For most classes of AGN, for BL Lac objects and for radio-loud quasars, we find no excess coincidences above random expectation, and we give upper limits for their burst emission rate. However, surprising evidence is found for a positional correlation between gamma-ray bursts and radio-quiet quasars. A total of 134 selected bursts with a position error radius <1.8d and the nearest and intrinsically brightest radio-quiet quasars (M_v<-24.2 and z<1.0) have a probability of >99.7% to be associated with each other. An analysis of a smaller sample of well-localized interplanetary network gamma-ray burst positions supports this result. This correlation strongly favours the cosmological origin of gamma-ray bursts and enables to estimate its distance scale. The average luminosity of those gamma-ray bursts which we associate directly with radio-quiet quasars is of the order of 4*10^52 erg (assuming isotropic emission). 
N. Schartel (ESA Madrid), H. Andernach (ESA Madrid + Univ. Guanajuato,   Mexico), J. Greiner (MPE Garching)