High-energy transient events from Scorpius X-1 and Cygnus X-1

Abstract

We present evidence that the X-ray binaries Scorpius X-1 and Cygnus X-1 are responsible for high-energy transient events which have been cataloged in the CGRO BATSE 3B Gamma-ray burst (GRB) catalog as classical GRBs. We locate bursts in the 3B catalog which are positionally consistent with these binaries and compare the observed burst distribution properties with those found from an ensemble of randomly generated 3B catalogs and from repeater models. Two 3B cataloged GRBs that are likely high-energy transient events from Scorpius X-1; based on the fact that they occurred on the days with the two brightest “daily averages” in the Scorpius X-1 LAD light curve. We find that GRBs are emitted from Sco X-1 at the 99% confidence level. Numerous GRBs are emitted by Cygnus X-1 and removed by the BATSE team. We find that the some of the bursts remaining in the BATSE 3B catalog are probably high-energy transient events from Cygnus X-1 based on the anomalously low V/Vmax for the region near Cygnus X-1 as determined f...