GCN Circular 41162

S. P. R. Shilling (Lancaster U.) and P. A. Evans (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 250725A
880 s after the BAT trigger (Evans et al., GCN Circ. 41152
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 ).
No optical afterglow consistent with the enhanced XRT position
(Osborne et al., GCN Circ. 41153
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 ) 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           880         1029          147         >21.0
white              880         2562          322         >21.2
v                 1036         2439          175         >19.6
b                 1134         2537          175         >20.1
u                 1110         2340          156         >20.1
w1                1085         2488          175         >19.6
w2                1704         1898           39         >19.5

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.114 in the direction of the burst
(Schlegel et al. 1998).