GCN Circular 17302
Paul Kuin (MSSL/UCL) reports on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of MAXI GRB 150110C 54ks after the trigger. No optical afterglow consistent with the XRT position (Page, GCN Circ. No. 17301) 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 54238 59786 1896 >20.9 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.04 in the direction of the burst (Schlegel et al. 1998).