GCN Circular 32470
Subject
GRB 220813A: Swift/UVOT Detection
Date
2022-08-14T09:55:19Z (2 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) and M. G. Bernardini (INAF-OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220813A
100 s after the BAT trigger (Bernardini et al., GCN Circ. 32465).
A source consistent with the XRT position (Osborne et al.,
GCN Circ. 32466) is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 05:26:07.60 = 81.53166 (deg.)
Dec (J2000) = -33:00:59.0 = -33.01638 (deg.)
with an estimated uncertainty of 0.52 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT photometric
system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures
are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 100 250 147 19.67 +/- 0.11
v 589 1581 117 >18.3
b 515 1506 97 >19.6
u 258 1652 360 >20.6
w1 638 1630 117 >19.6
m2 613 1605 117 >20.1
w2 564 1556 117 >20.0
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.022 in the direction of the burst
(Schlegel et al. 1998).