GCN Circular 31482
Subject
GRB 220117A: Swift/UVOT Upper Limits
Event
Date
2022-01-18T14:13:23Z (5 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL) and A. Melandri (INAF-OAB) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220117A 162 s after the BAT trigger
(Melandri et al., GCN Circ. 31466).
No optical afterglow consistent with the XRT position (Beardmore et al. GCN Circ. 31472) 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 162 311 147 >20.5
u_FC 320 570 246 >20.0
white 162 998 306 >20.7
v 650 845 39 >18.4
b 576 770 39 >19.4
u 320 744 265 >20.0
w1 700 720 19 >19.3
m2 675 869 39 >18.7
w2 626 821 39 >18.9
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of
E(B-V) = 0.028 in the direction of the burst (Schlegel et al. 1998).