GCN Circular 15545
Subject
GRB 131128A: Swift/UVOT Detection
Event
Date
2013-11-29T11:54:03Z (13 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (UCL-MSSL) and E. Sonbas (NASA/GSFC/Adiyaman Univ.)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 131128A
91 s after the BAT trigger (Sonbas et al., GCN Circ. 15533).
A source consistent with the optical position (Xu et al., GCN Circ. 15535)
and the enhanced Swift-XRT position (Goad et al., GCN Circ 15538) is
detected in the first UVOT white exposure only. A USNO-B1 catalogued star
heavily contaminates the position of the optical candidate afterglow
making the measurement very complicated.
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 (FC) 91 241 147 19.11 +/- 0.11
white 583 1181 206 >21.44
u (FC) 303 552 245 >20.2
u 303 1130 285 >20.3
v 632 1231 78 >19.0
b 558 1155 58 >19.8
w1 683 1275 53 >18.9
m2 657 1255 78 >19.0
w2 608 1206 78 >19.4
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.07 in the direction of the burst