GCN Circular 16918

A. A. Breeveld (UCL-MSSL) and E. Troja (NASA/GSFC/UMCP) report on behalf 
of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 141015A 
21301 s after the BAT trigger (Troja et al., GCN Circ. 16909
Not found
 
 
).
No optical afterglow consistent with the XRT position (Evans et al. GCN 
Circ. 16913
Not found
 
 
) is detected in 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         21301        21451          147         >20.5
white            21301        23280         1033         >21.5
v                27071        27978          885         >19.8
b                21461        22368          885         >20.8
w1               28890        29661          759         >20.1
m2               27983        28883          886         >20.3
w2               23286        23906          610         >20.1

The magnitudes in the table are not corrected for the Galactic 
extinction due to the reddening of E(B-V) = 0.51 in the direction of the 
burst (Schlegel et al. 1998).