TITLE: GCN CIRCULAR NUMBER: 10885 SUBJECT: GRB100625A : MOA optical upper limit DATE: 10/06/25 21:19:35 GMT FROM: Suzuki Daisuke at MOA-II D. Suzuki, F. Hayashi, S. Kobara, T. Sako, H.Naito, K. Omori (STE Lab, Nagoya Univ.) on behalf of the MOA Collaboration report: We searched for an optical afterglow of GRB 100625A (GCN 10884, S. T. Holland et al.) starting from 18:49 UT on 2010 June 25th (17 minutes after the BAT trigger) with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand. In a single image of a 60sec exposure with a wide-band Red filter (center wavelength ~ 750nm and FWHM ~ 250nm), we did not find any object within the error circle of the Swift XRT source position (GCN 10884). A 3 sigma upper limit is set in the I magnitude at 22.77 mag. This photometry was done by using the DoPhot and calibrated against the USNO-B1.0 catalog stars, and not corrected for the Galactic extinction.