Could Grb 060614 and Its Presumed Host Galaxy Be a Chance Superposition?

Abstract

The lack of an observed supernova associated with GRB 060614 appears to require a new paradigm for the formation of (a subset of) long-duration GRBs. This requirement is based on the presumed low redshift of the burst, which was inferred from the spatial coincidence of the afterglow with a z = 0.125 galaxy. We explore the possibility that this low-redshift galaxy is a chance superposition along the line of sight to GRB 060614. We examine the galaxy distribution of the field of GRB 060614 and find that the probability of a chance association with a galaxy at least as bright as the putative host is only∼ 0.5−1.9%. However, for the current ensemble of ≈ 180 Swift GRBs it is likely that several such coincidences have occurred, and given the “non-standard” nature of GRB 060614 it is not implausible that this is one such occurrence. Thus the conclusion that GRB 060614 requires a revision to the formation paradigm for long-duration GRBs should be approached with caution. Subject headings: gamma rays: bursts

2 Figures and Tables

Cite this paper

@inproceedings{Cobb2006CouldG0, title={Could Grb 060614 and Its Presumed Host Galaxy Be a Chance Superposition?}, author={Bethany E. Cobb and Charles D . Bailyn and P . G . van Dokkum and Priyamvada Natarajan}, year={2006} }