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GCN Circular 4943

GRB060331: Swift/UVOT upper limits
2006-04-03T10:10:57Z (18 years ago)
Patricia Schady at MSSL/Swift <>
P. Schady (UCL-MSSL), on behalf of the Swift/UVOT team

The Swift/UVOT observed the field of HETE II transient H4043 (Fenimore et al. 
GCN 4938) at two separate epochs starting at 16:53 UT and 18:29 UT. A 575s 
coadded exposure from the first epoch of observations taken in white reveals no 
new source in the field of view down to a 5-sigma magnitude upper limit of 
19.9. In both epochs no source is detected in summed images from any of the 
filters used down to the following 5-sigma upper limits.

1st Epoch
Filter  Date Obs.     Exp (s) 5sigUL(mag)
B       17:08:07 UT   885     20.3
U       16:52:56 UT   885     20.0
White   17:23:18 UT   575     19.9

2nd Epoch
Filter  Date Obs.     Exp (s) 5sigUL(mag)
B       18:59:13 UT   605     19.8
U       18:44:02 UT   885     20.0
UVW1    18:28:55 UT   886     19.4

where Date Obs. is the time of the beginning of the observations. These 
magnitudes are not corrected for Galactic extinction; E(B-V)=0.148.
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