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arXiv · 0904.2566

Are Swift Long-Lag Gamma-Ray Bursts in the Local Supercluster?

Limin Xiao·Bradley E. Schaefer
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Abstract

A sample of 18 long-lag (tau_{lag} > 1 s) Gamma-Ray Bursts (GRBs) has been drawn from our catalog of all Swift long GRBs. Four different tests are done on this sample to test the prediction that a large fraction of long-lag GRBs are from our Local Supercluster. The results of these four tests come out that: (1) the distribution of these GRBs shows no tendency towards the Supergalactic plane; (2) the distribution shows no tendency towards the Virgo or Coma Cluster; (3) no associated bright host galaxies (m <=15) in the Local Supercluster are found for any of the 18 GRBs; (4) 17 of these 18 GRBs have redshifts of z>0.5, which are too far to be in the Local Supercluster. All these results disproved the hypothesis that any significant fraction of long-lag GRBs are from Local Supercluster. Hence these long-lag GRBs can not be counted in the calculation of LIGO detection rates. An explanation of why we can detect long-lag GRBs at high redshift is presented.

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Limin Xiao, Bradley E. Schaefer. 2009-04-16. Are Swift Long-Lag Gamma-Ray Bursts in the Local Supercluster?. https://doi.org/10.1088/0004-637x%2F698%2F1%2F803

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