GCN Circular 11955
Subject
GRB 110420B: Swift/UVOT Upper Limits
Event
Date
2011-04-21T14:29:56Z (15 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL) & B. Sbarufatti (INAF-OAB/IASFPA) report on behalf of the Swift-UVOT team
The Swift/UVOT began settled observations of the field of GRB 110420B
2562 s after the BAT trigger (Sbarufatti et al., GCN Circ. 11944).
No optical afterglow is found within the BAT error circle.
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 2562 2711 147 >20.6
white 2562 4765 540 >20.5
v 3541 16124 1322 >19.9
b 2926 22368 621 >20.4
u 2720 28151 1730 >20.0
w1 3950 28007 2844 >19.6
m2 3745 27103 2416 >19.5
w2 3336 15211 1279 >19.7
###############################################################
The values quoted above are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).