TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3965 SUBJECT: GRB 050911, optical observations DATE: 05/09/11 23:31:57 GMT FROM: Alberto Castro-Tirado at LAEFF-INTA P. Tristram (Univ. of Canterbury, New Zealand), A. J. Castro-Tirado, S. Guziy, A. de Ugarte Postigo, M. Jelinek, J. Gorosabel (IAA-CSIC, Granada, Spain), and Ph. Yock (Univ. of Auckland, New Zealand) report: "We have imaged the GRB 050911 error box provided by Swift/BAT (Page et al. GCN 3961) with the 0.6m telescope (+MOA camera) at Mt. John Observatory. 5 x 300s second integrations in the wide R-band filter were taken starting at 16:35:16 UT (i.e. 36 min after burst). Within the refined Swift/BAT error box (Tueller et al. GCN 3964), the coadded image does not reveal any variable object down to R~21 when comparing to the DSS-2." This message can be quoted.