TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1265 SUBJECT: GRB020305, optical observations DATE: 02/03/09 21:40:49 GMT FROM: Rene Hudec at AIO M. Jelinek, P. Kubanek, M. Nekola, R. Hudec & BART team, Astronomical Institute, Academy of Sciences of the Czech Republic, Ondrejov, report: The BART robotic telescope at the Ondrejov Observatory observed the error box of the GRB020305 (HETE trigger 1939) at March 5.93249 UT i.e. 10.45 hours after the burst. Observation was done by two different cameras in six groups of eleven (pairs of) images, with 120s exposures. Every group of images took approx. 35 minutes (0.02430d) to obtain. Series were beginning at: 2002 March 5.93249, 5.96767, 6.01779, 6.06597, 6.11422 and 6.16356 UT. The observing conditions were not optimal due to some sort of cirrus on the sky. No new optical object was found in reported error box. Following magnitude limits were obtained: Wide Field Camera (D=64mm, f/1.7), unfiltered, full HETE error box coverage, gives single image limiting magnitude 14.5 in 2 minute integration. Narrow Field Camera (D=254mm, f/6.3), Johnson R-band, single-image limiting magnitude 17.0, when combining all 66 obtained NF images there is a limiting magnitude of 18.5 with effective integration time of 132 min. The Narrow Field Camera FOV is 20 x 20 arcmin (~ 20% of the HETE and ~50% of the combined HETE/IPN error box) centered approx 7 arcmin to the west and 4 arcmin to the south from the center of the HETE reported position (the image center has RA12:42:30, DEC -14:37). Further image analysis is planned.