GCN Circular 19449
Subject
GRB 160521B: Swift/UVOT Upper Limits
Event
Date
2016-05-22T17:23:14Z (10 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of GRB 160521B centered on
the LAT position (Axelsson et al., GCN Circ. 19444) 41882 seconds after
the trigger. The exposures for the optical filters (white, b, and u)
cover about 20% of the LAT statistical error circle, and
the uv filters (uvw1 and uvm2) cover about 44%.
Only the exposures with the uv filters cover
the possible XRT counterpart (Page et al., GCN Circ. 19448).
The preliminary upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 42794 43127 324 >20.8
b 41882 49001 1180 >20.7
u 47789 48695 885 >20.2
uvw1 46882 54226 1578 >20.1
uvw2 52616 53065 886 >20.4
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).