GCN Circular 13037
Subject
GRB 120311A: Swift/UVOT Upper Limits
Event
Date
2012-03-11T15:16:25Z (14 years ago)
From
Patricia Schady at MPE/Swift <msslba@googlemail.com>
S. R. Oates (MSSL-UCL) and C. B. Markwardt (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 120311A
3164 s after the BAT trigger (Markwardt et al., GCN Circ. 13032).
No optical afterglow, consistent with the refined XRT position
(Goad et al .,GCN Circ 13035) or optical position reported by the
Liverpool Telescope (Melandri et al., GCN Circ 13033), is detected within
the initial UVOT exposures. Preliminary 3-sigma upper limits using
the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373)
for the first finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 3164 3314 147 >16.4
white 3164 16486 2114 >16.5
v 3321 20754 1454 >15.8
b 4141 15574 1224 >16.4
u 3936 5571 393 >16.3
w1 3731 5366 393 >17.7
m2 3526 5161 393 >19.0
w2 4552 17272 1850 >19.2
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.13 in the direction of the burst
(Schlegel et al. 1998).