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GCN Circular 16808

GRB 140909A: Swift detection of a GRB
2014-09-09T17:59:24Z (10 years ago)
David Palmer at LANL <>
David Palmer reports on behalf of the Swift Team:

In two successive 64-second images, beginning at 06:56:51, BAT detected a source at a consistent
location.  Although the individual images were below threshold, the combined detection
is highly significant, in excess of 8 sigma.  A 320 s image that includes the data
from both 64 s images indicates additional flux outside of the 128 s time interval.

The BAT on-board calculated location is RA,dec = 193.638,63.494 (J2000), which is
  RA(J2000) =  12h 54m 33s
  Dec(J2000) = +63d 29� 38�

As is usual for image triggers, there is no obvious variation in the BAT lightcurve.

Because the individual images were below threshold, Swift did not automatically
slew to the location.  However, a ToO has been requested.

David Palmer   (505)665-6863 (voice)   (505)665-4414 (fax)
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