GCN Circular 22158
Subject
GRB 171123A: Swift/UVOT Upper Limits
Date
2017-11-24T13:06:31Z (6 years ago)
From
Sam Emery at MSSL-UCL <samuel.emery.15@ucl.ac.uk>
S.W.K. Emery (UCL-MSSL) and P. A. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 171123A
94 s after the BAT trigger (Evans et al., GCN Circ. 22148).
No optical afterglow consistent with the XRT position
(Goad et al. GCN Circ. 22150)
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 94 243 147 >20.9
u_FC 308 557 246 >20.5
white 94 2397 489 >21.0
v 637 2447 214 >18.8
b 563 2373 194 >19.7
uvw1 13669 18855 1209 >20.7
uvm2 12763 13663 886 >20.6
uvw2 23870 35081 1032 >21.1
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).