TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1405 SUBJECT: GRB020531: optical observations DATE: 02/06/02 09:41:10 GMT FROM: Weidong Li at UC Berkeley KAIT/LOSS W. D. Li, A. V. Filippenko, and R. Chornock (UC Berkeley) report on behalf of the Lick Observatory and Tenagra Observatory Supernova Search (LOTOSS): "We have observed a rectangle region of about 21' x 7' around the position of GRB020531 (Richer et al., GCN #1399) with the 0.8-m Katzman Automatic Imaging Telescope (KAIT) with 4x120s and 4x300s unfiltered exposures beginning on May 31 04:56 UT, 2002, less than 4.5 hours after the burst. The individual exposure reaches or exceeds the POSS II plate limit, R~20.5. The same region was imaged again beginning on Jun 1 06:05 UT, 2002. We used image subtraction to compare the observations from these two nights, but have not yet found any bright new stationary objects. We identified two asteroids whose J2000 coordinates are reported below: Asteroid 1: mag about 19.5 R. A. = 15h14m35s.85, Decl. = -19 23'49".0 at May 31 4:57 UT R. A. = 15h14m35s.70, Decl. = -19 23'48".7 at May 31 5:02 UT Asteroid 2: mag about 20.0 R. A. = 15h14m54s.51, Decl. = -19 24'35".8 at May 31 5:06 UT R. A. = 15h14m54s.36, Decl. = -19 24'36".4 at May 31 5:10 UT." This message is citable.