TITLE: GCN CIRCULAR NUMBER: 12295 SUBJECT: GRB 110820A: CQUEAN izY Observation DATE: 11/08/21 08:14:40 GMT FROM: Myungshin Im at Seoul Nat U Myungshin Im, Won-Kee Park (CEOU/Seoul National Univ), Soojong Pak, Giseon Baek, and Youngseok Oh (Kyunghee University) We observed GRB 100820A (Troja et al. GCN 12288) with i,z,and Y-filters using CQUEAN camera (the Camera for QUasars in the Early uNiverse) on the 2.1m telescope at the McDonald observatory. The observation started at 2010 August 21, 05:12:48 UT, about 11.5 hrs after the BAT trigger. In a stacked i-band image (3 x 300 sec), we identify a faint object within the error circle of the enhanced XRT position (Beardmore et al. GCN 12291). The position of the i-band source is RA=22:52:49.49 Dec=70:17:53.6 with a positional error of ~0.5". We are carrying our further observations to examine variability of the source.