GCN Circular 31682
Subject
GRB 220302A: Swift/UVOT Upper Limits
Date
2022-03-05T03:37:18Z (2 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and E. Troja (NASA/GSFC/UMCP)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220302A
32464 s after the BAT trigger (Troja et al., GCN Circ. 31661).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 31666) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 32464 32614 147 >19.9
white 32464 32614 147 >19.9
v 32621 33528 885 >19.2
m2 33533 34194 651 >19.7
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.217 in the direction of the burst
(Schlegel et al. 1998).