GCN Circular 13932
Subject
GRB 121027A: Swift/UVOT Possible Detection
Event
Date
2012-10-30T17:59:26Z (14 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and P. A. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 121027A
77 s after the BAT trigger (Evans et al., GCN Circ. 13906).
A source consistent with the XRT position (Beardmore et al. GCN Circ. 13916)
and the nIR position (Starling et al. GCN Circ. 13911)
is weakly detected in the initial UVOT exposures.
The preliminary detection 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 77 1192 353 21.55 +/- 0.25
v 619 1239 75 >19.5
b 544 1167 58 >19.7
u 289 1143 285 >20.6
w1 668 1118 58 >19.8
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).