GCN Circular 13538
Subject
Swift Trigger 529076 is from Swift J1910.2-0546 and is not a GRB
Date
2012-07-29T18:16:45Z (13 years ago)
From
Hans Krimm at NASA-GSFC <hans.a.krimm@nasa.gov>
H. A. Krimm (CRESST/GSFC/USRA) for the Swift team
Further analysis of the Swift/BAT event data from Trigger 529076 (GCN Circ
13527, Chester et al) yields a significance of 5.4-sigma. Over the time range
we have data (T-120 to T+180 sec), the mask-weighted light curve shows constant
emission with no significant features on time scales typical of a gamma-ray
burst. Therefore we conclude that this trigger was not due to a GRB.
The XRT and UVOT positions reported in GCN Circ 13530 are consistent within
reported errors of the position for Swift J1910.2-0546 (ATel #4144; Rau,
Greiner, and Schady). Also this source has been steadily brightening in the BAT
hard X-ray transient monitor (average of 0.021 � 0.001 ct/s/cm^2 (~100 mCrab) in
the 15-50 keV band for 28-July-2012). Therefore we conclude that Trigger 529076
was caused by Swift J1910.2-0546, but that low statistics in the trigger
interval yielded a BAT position inconsistent with this known source.
[GCN OPS NOTE(29jul12): Per author's request, "13530, Ukwatta" was changed to "13527, Chester".]