TITLE:   GCN CIRCULAR
NUMBER:  10452
SUBJECT: GRB 100219A: GAO 150cm telescope Optical Observation
DATE:    10/02/26 01:01:58 GMT
FROM:    Kenzo Kinugasa at Gunma Astro. Obs/Japan  <kinugasa@astron.pref.gunma.jp>

K. Kinugasa, S. Honda, H. Takahashi, H. Taguchi, O. Hashimoto 
 (Gunma Astronomical Observatory) report:

 The position of GRB 100219A (Rowlinson et al., GCN 10430) was observed
with the 150 cm telescope of Gunma Astronomical Observatory. Starting at 
16:06:16 UT on Feb.19 (0.84 hour after the trigger), both Rc and Ic 
frames were acquired for sets of 5 x 3-min exposures.

 Inside the XRT error circle (Evans et al., GCN 10437), we detected the
optical counterpart reported by Jakobsson et al. (GCN 10438), Kruehler 
et al. (GCN 10439), and Kuroda et al. (GCN 10440) in Rc and Ic stacked 
images. We estimated the Rc and Ic magnitudes relative to USNO-B1.0 R2 
and I magnitudes, respectively.

mid-UT     T0+(d)     exp       mag.            
-----------------------------------------------------
16:15:24   0.0414    5x3min     Rc=20.5+-0.2     
16:34:45   0.0549    5x3min     Ic=19.6+-0.3     
-----------------------------------------------------