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GCN Circular 17716

Confirmation that Swift trigger 638217 is not an astrophysical source
2015-04-17T14:49:12Z (9 years ago)
Hans Krimm at NASA-GSFC <>
H. A. Krimm (CRESST/GSFC/USRA) and B. Sbarufatti (INAF-OAB/PSU) report on behalf 
of the Swift Team:

We conclude that Swift trigger #638217 (Gehrels, et al., GCN Circ. 17712) was
the result of noise fluctuations and is not due to a GRB or other astrophysical

We have analyzed the BAT data set from T-239 to T+440 sec from the recent
telemetry downlink.  We find that there is no sign of significant emission from
the trigger location at any point in this interval.

XRT observations in Photon Counting mode data started 152 s after the BAT 
trigger. In 1.9 ks of PC data no source is detected inside the BAT error circle. 
The three sigma upper limit is 9.5e-3 counts/second.
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