GCN Circular 17800
Subject
Confirmation that Swift Trigger 639636 is not astrophysical
Date
2015-05-03T01:25:25Z (10 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
S. D. Barthelmy (GSFC), A. Maselli (INAF-IASFPA), M. Siegel (PSU), P. Kuin (MSSL)
report:
We conclude that Swift trigger #639636 (Maselli, et al., GCN Circ. 17799)
was the result a noise fluctuation in BAT and is not due to a GRB or other
astrophysical event.
We have analyzed the BAT data set from T-239 to T+680 sec from recent
telemetry downlinks. We find that ground analysis results in the significance
dropping to 4.1 sigma from T+0 to T+60 s.
Using 4.4 ks of XRT data, there is no significant counterpart detected
within the BAT error circle at a three sigma upper limit of 2.84E-03 cts/s.
The UVOT finding chart shows no new source to a limit of 19.6 mag in white.