GCN Circular 3603

S. Rosen (MSSL), S. Vaughan (Leicester), R. Fink
(GSFC-SPSYS), M. Chester (PSU) report on behalf of
the Swift UVOT team:

Using summed images from Swift/UVOT of the field of
GRB 050713B, taken from 136 seconds after the BAT
trigger, no new source is detected within the XRT
error circle (Vaughan et al., GCN 3590
Not found
 
 
) in any of
the six filters down to the following 3-sigma
magnitude upper limits:

Filter   Exposure (s)  T_mid (s)   3-sig limit
V        252           598         19.26
B         88           624         19.58
U         88           610         19.31
UVW1      88           596         19.46
UVM2      88           582         19.83
UVW2      88           639         19.87

where T_mid is the mid-point of the summed observation.

We caution that the instrument is not yet fully
calibrated and that the magnitude limits presented here
may need to be refined.