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GCN Circular 18586

Swift-BAT trigger 663164 is not a burst.
2015-11-12T10:59:47Z (9 years ago)
Phil Evans at U of Leicester <>
P. A. Evans (U Leicester), H. A. Krimm (CRESST/GSFC/USRA),
K. L. Page (U Leicester) and B. Sbarufatti (INAF-OAB/PSU) report on
behalf of the Swift Team:

At 10:28:11 UT, the Swift Burst Alert Telescope (BAT) triggered 
(trigger=663164) on what appears to be noise during the count rate 
rise associated with entry into the SAA.  The image significance 
is low (6.5 sigma) and there is no significant peak in the light 
curve.  Thus we believe that this trigger is not due to a GRB or
other astrophysical event. 

The XRT began observing the field at 10:29:46.6 UT, 94.8 seconds after
the BAT trigger. Initially XRT centroided on a cosmic ray. Further
XRT data were not gathered until 1491 s after the trigger, due
to SAA passage. No source was detected in 132 s of promptly-downlinked
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