TITLE:   GCN CIRCULAR
NUMBER:  11594
SUBJECT: GRB 101225A: CQUEAN optical observation
DATE:    11/01/22 15:52:20 GMT
FROM:    Won-Kee Park at Seoul Nat U/Dept.Physics and Astronomy/CEOU  <wkpark@astro.snu.ac.kr>

Won-Kee Park, Myungshin Im, Changsu Choi (Seoul National Univ.),
Hyeonju Jeong, Juhee Lim, and Soojong Pak (Kyung Hee Univ.)


The field of GRB 101225A was observed with CQUEAN, an optical
CCD camera attached at the 2.1m telescope at McDonald Observatory,
USA. The observation was carried out from 01:16:23 UT, Dec. 26, 2010,
with i, r, z, and Y filters, with exposures of 3 * 300 secs for each
band.

The afterglow was clearly visible on i and r-band images at
the same position reported by Xu et al.(GCN 11495). We obtained
the preliminary magnitude of the afterglow on the stacked i-band
image calibrated with the neighboring USNO B-1.0 stars:
R = 22.60 +- 0.19 at 01:42:47 UT. Further analysis of the data is
ongoing.