GCN Circular 25089
Subject
GRB 190718A: Swift/UVOT Upper Limits
Event
Date
2019-07-18T16:18:19Z (6 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (U.Warwick) and V. D'Elia (SSDC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190718A
70 s after the BAT trigger (D'Elia et al., GCN Circ. 25082).
No optical afterglow consistent with the XRT position
(Evans et al., GCN Circ. 25084) 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 70 219 147 >20.9
u_FC 282 532 246 >20.0
white 70 1184 353 >21.0
v 612 1061 78 >18.3
b 538 1159 58 >19.1
u 282 4874 307 >20.0
w1 661 4847 235 >19.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).