GCN Circular 32488
Subject
GRB 220826A: Swift/UVOT Detection
Date
2022-08-26T18:47:37Z (2 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
N. P. M. Kuin (UCL-MSSL) and R. Caputo (GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 220826A
91 s after the BAT trigger (Caputo et al., GCN Circ. 32484).
A source consistent with the XRT position (Beardmore et al. GCN Circ. 32485)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 13:45:38.51 = 206.41047 (deg.)
Dec (J2000) = -44:02:19.2 = -44.03866 (deg.)
with an estimated uncertainty of 0.45 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 91 240 147 18.12 +/- 0.05
v 632 827 39 >18.4
b 559 753 39 >18.6
u 303 553 246 18.69 +/- 0.13
w1 682 702 19 >17.7
m2 831 851 19 >17.8
w2 608 802 39 >19.2
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.110 in the direction of the burst
(Schlegel et al. 1998).