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GCN Circular 4426

Swift-BAT trigger 175653 is probably not a GRB
2006-01-03T04:41:19Z (18 years ago)
Scott Barthelmy at NASA/GSFC <>
D. Grupe (PSU), S. Barthelmy (GSFC), D. Burrows (PSU),
M. Chester (PSU), N. Gehrels (GSFC), C. Gronwall (PSU),
S. Immler (GSFC), J. Kennea (PSU), F. Marshall (GSFC),
T. Sakamoto (GSFC)
on behalf of the Swift team:

The Swift-BAT trigger (trigger=175653) at ~04:03 UT on 03 January 2006
is probably not due to a GRB or any other astrophysical source.
The background is high while entering the SAA.  This was a single-sided
trigger criterion which is susceptible to rising backgrounds.

The XRT began observing the field in the SAA and attempted to find a 
centroid of a bright source in the field of view, but failed to find a 
source.  This is consistent with a non-burst origin for this event, but 
this is not conclusive, as we only succeed in on-board centroids 
approximately 40% of the time due to faint afterglows.

This GCN Notices have the same incorrect trigger time as did
the previous burst.  This problem is being worked.
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