Ross P. Church, Andrew J. Levan, Melvyn B. Davies, Nial Tanvir
We compare the observed spatial offsets of short gamma-ray bursts from their
host galaxies with their predicted distributions, assuming that they originate
in double neutron star binaries that form from field stars. We find that, for
the majority of bursts, this model is sufficient to explain the observed
offsets, although there is a trend towards larger offsets than predicted. One
burst, GRB 060502B, has an offset that is clearly anomalous. We discuss
possible reasons for the large offsets, including host galaxy
misidentification, and suggest that some of the largest-offset bursts may
originate in the merger of double neutron star binaries that form dynamically
in the cores of globular clusters.
View original:
http://arxiv.org/abs/1110.4209
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