Fast transient X-rays and gamma ray bursts—are they stellar flares?

Abstract

Short period transient X-ray emissions (FTX) have been observed from several sources in the sky and the largest single group of objects identified with such sources are active stars - flare stars and RS CVn binaries. We study the number, source and flux distribution of the fast transient X-ray sources and show that all the FTX emission can be treated as flares in the interbinary regions of active stars. We further suggest that the FTX emission is a common feature of the gamma ray bursts (GRBs). We discuss the evidence for the similarity between the hard X-ray flares and GRBs. We examine the possibility that the gamma ray bursts are the impulsive precursors of FTX originating from active stars with large scale magnetic activity.