TITLE: GCN CIRCULAR NUMBER: 6009 SUBJECT: GRB 070110: UVOT Observations of a Candidate Afterglow DATE: 07/01/11 00:29:04 GMT FROM: Pete Roming at PSU P. Roming (PSU), P. T. Boyd, and H. Krimm (NASA/GSFC) report on behalf of the Swift UVOT team: The Swift/UVOT began settled observations of GRB 070110 104 seconds after the BAT trigger (Krimm et al., GCN Circ.6005). Analysis of the merged Swift/UVOT data obtained on 2007-01-10 shows that the candidate optical afterglow was detected in the White, V, B, and U filters, but not in the UV filters. The photometry results are given for the 7 UVOT filters below: Filter Tstart Tstop Exp Mag Error Significance White 104 5882 590 20.0 0.14 9.1 V 210 23205 2065 20.3 0.20 5.7 B 4046 29593 1568 20.9 0.17 7.1 U 5274 35376 3166 20.4 0.10 11.6 UVW1 5069 34757 3758 20.8 (3-sigma UL) UVM2 4864 33850 2739 21.1 (3-sigma UL) UVW2 4456 39315 1853 20.9 (3-sigma UL) There is marginal evidence for fading of the optical candidate but confirmation of its fading is pending further analysis. The values quoted above are not corrected for the expected extinction corresponding to E(B-V) of 0.014.