GCN Circular 29868
Subject
GRB 210419C: Swift/UVOT Upper Limits
Event
Date
2021-04-21T16:30:59Z (5 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and M. J. Moss (GWU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210419C
156 s after the BAT trigger (Moss et al., GCN Circ. 29834).
No optical afterglow consistent with the XRT position
(Beardmore et al. GCN Circ. 29839)
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 156 305 147 >20.83
white 6954 17801 254 >21.14
v 11428 28719 155 >19.22
b 6749 17713 1081 >21.37
u 313 408 93 >19.55
u 6544 22974 258 >20.20
UVW1 6339 22905 1082 >20.49
UVM2 6134 6334 196 >19.21
UVW2 10522 28626 1771 >20.84
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.010 in the direction of the burst
(Schlegel et al. 1998).