TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3081 SUBJECT: GRB 050309 : Lulin R-band observation DATE: 05/03/09 12:47:01 GMT FROM: Kuiyun Huang at IANCU GRB 050309 : Lulin R-band observation H.Hsieh, R.Mann (IfAUH) K.Y. Huang, W.H. Ip (NCU), Y. Urata, T. Tamagawa (RIKEN), Y. Qiu (BAO), Y.Q. Lou(THCA) on behalf of the East Asian collaboration report: We observed the SWIFT/BAT error region for GRB 050309 (trigger no. 107873) using Lulin 1-m telescope at Taiwan. We imaged a single R-band 300 sec exposure at 11.14 UT (~ 25 mins after the burst ). Compare with DSS-II image, no new object was found. The limiting magnitude is about 19 mag ( S/N=3 , with USNOB1.0 catalogue). This message may be cited.