GRB off-axis afterglows and the emission from the accompanying supernovae [HEAP]

http://arxiv.org/abs/1604.02151


Gamma-Ray Burst (GRB) afterglows are likely produced in the shock that is driven as the GRB jet interacts with the external medium. Long duration GRBs are also associated with powerful supernovae (SN). We consider the optical and radio afterglows of long GRBs for both blasts viewed along the jet axis (“on-axis” afterglows) and misaligned observes (“off-axis” afterglows). Comparing the optical emission from the afterglow with that of the accompanying SN, using SN 1998bw as an archetype, we find that only a few percent of afterglows viewed off-axis are brighter than the SN. For observable optical off-axis afterglows the viewing angle is at most twice the half-opening angle of the GRB jet. Radio off-axis afterglows should be detected with upcoming radio surveys within a few hundred Mpc. We propose that these surveys will act as “radio triggers,” and that dedicated radio facilities should follow-up these sources. Follow-ups can unveil the presence of the radio supernova remnant, if present. In addition, they can probe the presence of a mildly relativistic component, either associated with the GRB jet or the SN ejecta, expected in these sources.

Read this paper on arXiv…

A. Kathirgamaraju, R. Duran and D. Giannios
Mon, 11 Apr 16
21/52

Comments: 8 pages, 4 figures, 1 table