GCN Circular 30528
Subject
GRB 210723A: Swift/UVOT Upper Limits
Date
2021-07-27T06:16:48Z (3 years ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
GRB 210723A: Swift/UVOT Upper Limits
S. J. LaPorte (PSU) and Sbarrato (INAF-OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210723A
99 s after the BAT trigger (Sbarrato et al., GCN Circ. 30485).
No optical afterglow consistent with the XRT position
(Evans GCN Circ. 30486)
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 99 249 147 >20.6
u_FC 312 562 246 >19.2
white 99 1364 369 >20.6
v 641 1241 78 >18.2
b 567 1339 78 >19.3
u 312 1315 304 >19.4
w1 691 1290 58 >19.0
m2 666 1266 78 >18.8
w2 617 1217 78 >19.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.962 in the direction of the burst
(Schlegel et al. 1998).