GCN Circular 12434

N. P. M. Kuin (MSSL-UCL) and C. J. Saxton (UCL-MSSL)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 111008A
99 s after the BAT trigger (Saxton et al., GCN Circ. 12423
Not found
 
 
).
No optical afterglow consistent with the refined XRT position
(Beardmore et al., GCN 12425
Not found
 
 
; see also Levan et al. GCN 12426
Not found
 
 
,
Nardini et al. GCN 12428
Not found
 
 
, and Wiersema et al. GCN 12431
Not found
 
 
) is
detected in the initial UVOT exposures, consistent with the
redshift reported by Levan et al. and Wiersema et al..
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            99          249          147         >21.3
u_FC               311          561          246         >20.5
white               99         1359          373         >21.8
v                  641         1409           97         >19.0
b                  566         1335           78         >19.7
u                  311         1310          304         >20.6
w1                 690         1457           77         >19.2
m2                 666         1433           97         >21.0
w2                 617         1385           97         >19.8

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).