GCN Circular 23498
Subject
GRB 181202A: Swift/UVOT Detection
Date
2018-12-04T00:09:57Z (6 years ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
M. H. Siegel (PSU) and J. K. Cannizzo (NASA/UMBC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 181202A
86 s after the BAT trigger (Cannizzo et al., GCN Circ. 23482).
A source consistent with the XRT position
(Evans et al. GCN Circ. 23483)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 18:42:56.38 = 280.73491 (deg.)
Dec (J2000) = +27:57:35.0 = 27.95971 (deg.)
with an estimated uncertainty of 0.47 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
v 623 1540 117 >18.7
b 342 591 246 19.57 +/- 0.18
u (fc) 86 336 246 17.67 +/- 0.07
w1 672 1441 97 >19.6
m2 647 1560 112 >22.2
w2 598 1516 117 >20.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.14 in the direction of the burst
(Schlegel et al. 1998).