GCN Circular 9925
Subject
GRB 090916: Swift-XRT upper limit
Event
Date
2009-09-18T15:44:29Z (17 years ago)
From
Andy Beardmore at U Leicester <apb@star.le.ac.uk>
A. P. Beardmore, K. L. Page (U. Leicester) and E. Troja (NASA/GSFC/ORAU)
report on behalf of the Swift-XRT team :
Due to a Moon constraint, the Swift-XRT could not observe the field of
the BAT short GRB 090916 (Troja et al., GCN Circ. 9913) until 9.3
hours after the trigger. In 12.3 ks of Photon Counting mode data (from
33.5 to 126.6 ks after the trigger) we do not detect any source
within the BAT refined error circle of Barthelmy et al. (GCN Circ. 9915).
The 3 sigma upper limit 0.3-10 keV count rate is 8 x 10^-4 count s^-1,
which corresponds to an observed flux limit of 3 x 10^-14 erg cm^-2 s^-1
(assuming a typical count-to-observed flux conversion factor of
3.8 x 10^-11 erg cm^-2 ct^-1, Evans et al., 2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.