GCN Circular 12459
Subject
GRB 111018A: Swift/UVOT Upper Limits
Event
Date
2011-10-19T12:59:31Z (14 years ago)
From
Alice Breeveld at MSSL-UCL <aab@mssl.ucl.ac.uk>
A. A. Breeveld (MSSL-UCL) and F. E. Marshall (NASA/GSFC) report on
behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111018A
132 s after the BAT trigger (Marshall et al., GCN Circ. 12450). No
optical afterglow consistent with the refined XRT position (Goad et
al., GCN Circ. 12453) is detected in the initial UVOT exposures.
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 132 282 147 >21.1
white 132 7508 653 >21.8
v 462 12028 673 >20.2
b 388 6000 333 >20.9
u 291 5794 329 >20.6
uvw1 512 5590 314 >20.4
uvm2 487 5384 333 >20.2
uvw2 438 11672 1040 >21.4
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 2.16 in the direction of the burst
(Schlegel et al. 1998).