TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4055 SUBJECT: GRB 051001, optical observations at Mt. John DATE: 05/10/02 07:30:06 GMT FROM: Alberto Castro-Tirado at LAEFF-INTA P. Tristram (Univ. of Canterbury), M. Jelinek, A. J. Castro-Tirado, A. de Ugarte Postigo, S. Guziy, J. Gorosabel (IAA-CSIC, Granada) and Ph. Yock (Univ. of Auckland) report: "Following the detection of GRB 051001 by SWIFT (Krimm et al. GCN 4052), we have imaged the entire error box with the 0.6-m (+MOA camera) at Mt. John Observatory in wide R- and B-band filters (8 x 300-s each) starting on Oct 1.48 UT (i.e. 45 min after the event). We do not detect the object reported by Rol et al. (GCNC 4053) within the SWIFT/XRT error box (Moretti et al. GCN 4051) down to R about 21.5 ."