GCN Circular 30456
Subject
GRB 210712A: Swift/UVOT Upper Limits
Date
2021-07-12T23:12:07Z (3 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and B. Sbarufatti (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 210712A
91 s after the BAT trigger (Sbarufatti et al., GCN Circ. 30447).
No optical afterglow consistent with the enhanced XRT position
(Evans et al. GCN Circ. 30453) 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 91 241 147 >19.5
u_FC 304 554 246 >19.6
white 91 604 167 >19.5
b 560 579 19 >18.0
u 304 554 246 >19.6
w2 609 614 4 >17.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.076 in the direction of the burst
(Schlegel et al. 1998).