Extended GeV-TeV Emission around Gamma-Ray Burst Remnants and the Case of W49B

Abstract

We investigate the high-energy photon emission around gamma-ray burst (GRB) remnants caused by ultra– high-energy cosmic rays (UHECRs) from the GRBs. We apply the results to the recent report that the supernova remnant W49B is a GRB remnant in our Galaxy. If this is correct, and if GRBs are sources of UHECRs, a natural consequence of this identification would be a detectable TeV photon emission around the GRB remnant. The imaging of the surrounding emission could provide new constraints on the jet structure of the GRB.