TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3565 SUBJECT: GRB 050626 optical observations DATE: 05/07/06 09:37:17 GMT FROM: Javier Gorosabel at IAA-CSIC J. Gorosabel, A.J. Castro-Tirado, (IAA-CSIC), P. Tristam, T. Britton, Ph. Yock (Univ. of Auckland), S. Guziy, A. de Ugarte Postigo, M. Jelinek (IAA-CSIC), O. Bogdanov (Nikolaev State Univ.), report: "We have observed the error box of the INTEGRAL GRB 050626 (Gotz et al. GCN Circ. 3552). The observations were carried out ~4 hours after the gamma-ray event with the 0.6 m telescope at Mt. John Astronomical Observatory (MOA) using the MOA wide red filter (Texp=5x300s). We note the presence of Alpha Crucis (R=1.3) close to the error box, which produces a strong background gradient in our images. Thus, the deepness of the combined image ranges approximately from R~14 to R~20.5 depending on the position within the error box. Comparison with the DSS did not reveal any variable source in the INTEGRAL error box, including the position of the unlikely X-ray afterglow (Mangano et al., GCN Circ. 3564). At this X-ray source position the limiting magnitude of our combined image is approximately R~20." This message can be cited.