GCN Circular 29841
Subject
GRB 210419A: Swift/UVOT Upper Limits
Date
2021-04-20T15:49:41Z (3 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and S. L. Laha (GSFC/UMBC/CRESST)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210419A
136 s after the BAT trigger (Laha et al., GCN Circ. 29828).
No optical afterglow consistent with the XRT position
(Osborne et al., GCN Circ 29830)
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 136 286 147 >18.1
u_FC 294 544 246 >17.9
white 136 1027 333 >18.1
v 627 1079 58 >17.5
b 550 746 39 >17.7
u 294 721 265 >17.9
w1 677 871 39 >17.8
m2 651 1103 58 >18.3
w2 119 1053 67 >19.3
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.075 in the direction of the burst
(Schlegel et al. 1998).