GCN Circular 25128
Subject
GRB 190719C: Swift/UVOT Upper Limits
Date
2019-07-20T16:32:27Z (5 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) and E. Ambrosi (INAF-IASFPA)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 190719C
71 s after the BAT trigger (Ambrosi et al., GCN Circ. 25106).
No optical afterglow consistent with the XRT position 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 71 221 147 >20.6
u_FC 283 533 246 >20.6
white 71 756 186 >20.8
v 613 807 39 >18.7
b 538 732 39 >19.9
u 283 706 265 >20.5
w1 662 856 39 >19.2
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.04 in the direction of the burst
(Schlegel et al. 1998).
The upper limits are consistent with the faint candidate
afterglow reported by Malesani et al. (GCN Circ. 25110).