GCN Circular 31498
Subject
GRB 220118A: Swift/UVOT Detection
Date
2022-01-19T17:27:54Z (3 years ago)
From
Alexander Belles at PSU/Swift <aub1461@psu.edu>
A. Belles (PSU) and N. J. Klingler (GSFC/UMBC/CRESSTII)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220118A
99 s after the BAT trigger (Klingler et al., GCN Circ. 31490).
A fading source consistent with the XRT position
(Goad et al., GCN Circ. 31495) is detected in the initial
UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 12:49:04.52 = 192.26885 (deg.)
Dec (J2000) = +22:54:56.2 = 22.91562 (deg.)
with an estimated uncertainty of 0.44 arc sec. (radius, 90% confidence).
Preliminary detections 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
wh 119 268 145 17.73+/-0.07
wh 11382 11797 404 >20.26
u 276 454 175 17.33+/-0.12
b 10470 11377 885 >20.56
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.025 in the direction of the burst
(Schlegel et al. 1998).