GCN Circular 12528
Subject
GRB111103B Swift/UVOT Upper Limits
Event
Date
2011-11-03T21:26:25Z (14 years ago)
From
Patricia Schady at MPE/Swift <msslba@googlemail.com>
S. R. Oates (MSSL-UCL) and D. Grupe (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111103B
68 s after the BAT trigger (Grupe et al., GCN Circ. 12519).
No optical afterglow consistent with the XRT position (Goad et al., GCN Circ. 12525)
is detected in the initial UVOT exposures. The lack of an optical detection at the XRT
refined position excludes the possibility that the trigger is associated with the high proper
motion star (v~15mag) mentioned in Grupe et al. (GCN Circ. 12519) confirming that
the BAT trigger 506903 is a GRB.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC)
exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 68 218 147 >20.6
white 68 5055 344 >21.1
v 5266 5466 197 >19.1
b 4650 6161 270 >20.0
u 281 6081 297 >20.2
w1 5677 5876 197 >19.9
m2 5471 5670 197 >19.8
w2 5061 5261 197 >20.3
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.29 in the direction of the burst
(Schlegel et al. 1998).