GCN Circular 22248
Subject
GRB 171212A/Swift J1935.7+2036: Swift/UVOT Upper Limits
Event
Date
2017-12-12T22:16:30Z (8 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and A. Tohuvavohu (PSU) report on behalf of
the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 171212A 99
s after the BAT trigger (Tohuvavohu et al., GCN Circ. 22243).
No optical afterglow consistent with the enhanced XRT position (Evans et
al., GCN Circ. 22245) 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 >20.3
u_FC 257 507 246 >19.8
white 99 5510 383 >20.8
v 588 5921 235 >19.0
b 513 6581 275 >20.1
u 257 6536 468 >20.1
w1 638 6331 236 >19.5
m2 5926 6125 197 >19.3
w2 738 5716 216 >19.5
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 7.95 in the direction of the
burst (Schlegel et al. 1998).