GCN Circular 15476
Subject
GRB 131108A: Swift/UVOT Detection
Event
Date
2013-11-09T16:54:16Z (13 years ago)
From
Margaret Chester at PSU <chester@astro.psu.edu>
M.M. Chester and M. C. Stroh (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of the Fermi/LAT-detected
GRB 131108A 25920 s after the LAT trigger (Racusin et al., GCN Circ. 15464).
A source consistent with the XRT position (Stroh and Kennea GCN Circ. 15474)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 10:26:00.45 = 156.50187 (deg.)
Dec (J2000) = +09:39:44.1 = 9.66225 (deg.)
with an estimated uncertainty of 0.58 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 27746 28046 295 19.70 +/- 0.10
b 26833 27133 295 19.67 +/- 0.16
u 25920 26220 295 19.10 +/- 0.14
w1 31699 32599 886 20.96 +/- 0.33
m2 37465 37914 442 >20.6
w2 45446 49794 1069 >21.4
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).