TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4231 SUBJECT: GRB 051109B : Lulin Optical Observations DATE: 05/11/09 17:49:40 GMT FROM: Yuji Urata at RIKEN GRB 051109B : Lulin Optical Observations F.Y. Huang, K.Y. Huang, W.H. Ip (NCU), Y. Urata(RIKEN), Y. Qiu (BAO), Y.Q. Lou (THCA) on behalf of EAFON report: "The R and V band images of GRB 051109B (Tagliaferri et al. GCN 4222) were taken by Lulin 1-m telescope. The observation are started at 1.51 hours after the burst. No new source was detected at Swift/UVOT position (Tagliaferri et al. GCN 4222) and Swift/XRT (Campana et al. 4226) error regions. Compare with USNOB1.0 stars, the limiting magnitudes of our R and V band co-add images (300s x 3 for each band) are estimated as 21.0 and 20.0, respectively. This message may be cited."