TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2250 SUBJECT: GRB 030416: Optical Observations DATE: 03/05/27 15:19:05 GMT FROM: Jane Moran at U.North Carolina A. Henden, J. Silvay, J. Moran, R. Soule, D. Reichart, J. Schaefer, R. Canterna, and B. Scoggins report on behalf of the USNO, UWYO, and UNC GRB teams of the FUN GRB collaboration: We observed the entire 14 arcminute diameter error circle of XRF 030416 (Jernigan et al., GCN 2209) in BVRcIc beginning 15.4 hours after the burst, despite a bright moon. We report the following limiting magnitudes: Start Start Time Filter Integration Limiting Telescope Calibration Date Since GRB Time (sec) Magnitude Catalog (hours) x Pointings (3 sigma) Apr 17.103 15.391 Rc 6000 x 1 19.8 0.6-m RBO* USNO A2.0 Apr 17.143 16.361 B 300 x 1 20.1 1.3-m USNO USNO A2.0 Apr 17.149 16.502 V 300 x 1 20.9 1.3-m USNO ACT Apr 17.155 16.643 Rc 300 x 1 20.4 1.3-m USNO USNO A2.0 Apr 17.160 16.784 Ic 300 x 1 19.9 1.3-m USNO USNO B1.0 Apr 20.143 88.454 Rc 2160 x 1 22.3 1.3-m USNO USNO A2.0 * RBO = Red Buttes Observatory Using the image subtraction routine ISIS2 (Alard 2000, A&AS, 114, 363), we find no transient sources in either of our Rc images of April 17th when compared to our Rc image of April 20th.