GCN Circular 10999
S. Kobara, K. Omori, T. Sumi, D. Suzuki, H.Naito and T. Sako (STE Lab. , Nagoya Univ.) on behalf of the MOA Collaboration report : We searched for an optical afterglow of GRB100727A (GCN 10998, D. C. Morris et al.) starting from 07:12:3 UT on 2010 July 27 ( 90 minutes after the burst) with the MOA-II 1.8m telescope at Mt.John observatory in New Zealand. In a single image of a 300 sec exposure with a wideband 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 10998, D. C. Morris et al. ). A 3 sigma upper limit is set in the I magnitude at 21.6 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.