TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3276 SUBJECT: GRB 050416: Swift/UVOT detection of afterglow emission DATE: 05/04/16 19:13:08 GMT FROM: Patricia Schady at MSSL/Swift P. Schady (MSSL), T. Sakamoto (GSFC/NRC), K. McGowan (MSSL), P. Boyd (GSFC/UMBC), P. Roming (PSU), J. Nousek (PSU), N. Gehrels (GSFC), on behalf of the Swift UVOT team. The Swift Ultra-Violet/Optical Telescope (UVOT) began settled observations of the field of GRB 050416 (Sakamoto et al; GCN 3264) at 11:05:49 UT, 65s after the BAT trigger. A comparison of the 100s finding chart in the V filter against the Digitized Sky Survey reverals a new source inside the XRT error circle at RA = 12 33 54.56 Dec = +21 03 27.73 and consistent with the P60 positition reported by Bradley Cenko & Fox (GCN 3265). The V band magnitude is V = 19.38. The magnitude is based on preliminary zero-points, measured in orbit and will require refinement with further calibration. Further detailed analysis is ongoing.