GCN Circular 15615
A. A. Breeveld (UCL-MSSL) and M. De Pasquale (UCL-MSSL) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 131224A 10748 s after the INTEGRAL trigger (Mereghetti et al., GCN Circ. 15607). The field is very crowded and no optical afterglow consistent with the INTEGRAL position 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 initial exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag u 10748 18662 3918 >21.1 The magnitudes in the table are not corrected for the strong Galactic extinction due to the reddening of E(B-V) = 0.96 in the direction of the burst (Schlegel et al. 1998).