GCN Circular 12487

N. P. M. Kuin (MSSL-UCL) and S. Immler (CRESST/GSFC/UMD)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 111022A
815 s after the BAT trigger (Immler et al., GCN Circ. 12471
Not found
 
 
).
No optical afterglow consistent with the XRT position (Stratta et
al, GCN Circ. 12482
Not found
 
 
) is detected in the initial UVOT exposures.

The field is very crowded and the detection limits may be affected
in the white filter by the coincidence loss pattern from a
neighboring star.

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           815          965          147         >21.3
white              815         1287          186         >21.5
v                  972         1859          117         >18.7
b                 1071         1957          117         >19.9
u                 1046         1932          114         >18.9
w1                1021         1908          117         >19.5
m2                 996         1883          117         >21.0
w2                1120         1833           97         >19.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.66 in the direction of the burst
(Schlegel et al. 1998).