GCN Circular 35388
Subject
GRB 231216A: Swift/UVOT Upper Limits
Date
2023-12-17T10:03:34Z (10 months ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
Via
email
N. P. M. Kuin (UCL-MSSL) and Sbarrato (INAF-OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 231216A
191 s after the BAT trigger (Sbarrato et al., GCN Circ. 35378).
No optical afterglow consistent with the XRT position was 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
u_FC 191 441 246 >20.2
v 497 814 58 >18.5
b 447 1028 63 >20.0
u 191 1018 432 >20.8
w1 546 864 58 >19.5
m2 819 839 19 >18.3
w2 473 790 58 >19.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.082 in the direction of the burst
(Schlegel et al. 1998).