TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5185 SUBJECT: GRB060526: Optical counterpart from MIRO DATE: 06/05/30 03:02:47 GMT FROM: Kiran S Baliyan at Physical Research Lab, Ahmedabad,India K.S. Baliyan, S. Ganesh, H.O. Vats and J.K. Jain (MIRO-PRL, Ahmedabad, India) report: We observed the field around position of the optical counterpart of GRB060526 (Campana et al. GCN 5162, 5163; French & Jelinek GCN 5165; Rykoff et al. GCN 5166) beginning at 21:02 UT. The 1296*1154 CCD mounted on the 1.2 M telescope of Mt Abu IR Observatory, operated by Physical Research Laboratory, Ahmedabad- India, was used to observe OT in VRI bands with 180 second exposures. The afterglow is detected clearly in all the bands. We use Rc=16.484+/-0.01 mag for USNO B-1 star (RA=15:31:18.6, DEC=+00 17 34.9) as reference value to estimate preliminary R magnitudes for OT on May 26: 21:02:59 UT 18.65 +/- 0.19 21:09:26 UT 18.71 +/- 0.32 21:32:38 UT 19.06 +/- 0.19 22:44:22 UT 19.19 +/- 0.24 This message may be cited.