TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5306 SUBJECT: GRB060526: optical observations DATE: 06/07/13 14:05:29 GMT FROM: Alexei Pozanenko at IKI, Moscow V.Rumyantsev (CrAO), A.Pozanenko (IKI), M.Ibrahimov, I.Asfandyarov (MAO) on behalf of larger GRB follow up collaboration report: We observed the afterglow of GRB060526 (Campana et al. GCN5162) in Maidanak Astronomical Observatory (MAO) with 1.5 m telescope in R and B-passbands on May 26-31, and June 1-2. Additinnaly we recalibrated observation with CrAO Shajn 2.6m telescope (Rumyantsev et al. GCN5181). A photometry is based on the star USNO B1.0 RA=15 31 18.60 DEC=+00 17 35.00 R2=16.35 B2=16.42 already used in GCNs (Khamitov GCN5173, Morgan GCN5175, Kann GCN5172, Baliyan GCN5185). R-band photometry of the afterglow and upper limits are following: Mid_time (UT), Telescope, R_mag 26.7778 MAO1.5 17.98 +/- 0.01 26.7829 MAO1.5 18.06 +/- 0.01 26.7883 MAO1.5 18.11 +/- 0.01 27.7799 CrAO2.6 20.38 +/- 0.07 27.8143 CrAO2.6 20.47 +/- 0.06 27.8233 MAO1.5 20.43 +/- 0.04 28.8014 MAO1.5 21.31 +/- 0.13 29.8053 MAO1.5 22.06 +/- 0.11 30.8049 MAO1.5 22.84 +/- 0.24 31.7938 MAO1.5 23.52 +/- 0.32 01.8318 MAO1.5 >23.6 02.8648 MAO1.5 >23.8 The afterglow is clearly detected in B-filter up to May 29; B-photometry is underway. The message may be cited.