[vsnet-grb-info 4346] GRB 070223: Optical-IR observation with KANATA

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6133
SUBJECT: GRB 070223: Optical-IR observation with KANATA
DATE:    07/02/23 15:07:38 GMT
FROM:    Makoto Uemura at Hiroshima U  <uemuram at hiroshima-u.ac.jp>

M. Uemura, A. Arai, and T. Uehara (Hiroshima Univ.), 
report on behalf of the KANATA GRB team:

  We took optical and IR images of the field of GRB070223 (GCN 6125) at 
12:31-12:52 UT 23 Feb. using TRISPEC attached to the KANATA 
1.5-m telescope at Higashi-Hiroshima Observatory, Japan.  
We obtained 10 sets of V, J, and Ks-band images with a 123, 120, and 96-s 
exposure time, respectively.  
The images were calibrated with neighbor stars in the USNO A2.0 and 2MASS 
catalog.

We cannot significantly detect the optical and IR afterglows.  
at the position of the X-ray afterglow reported in GCN 6130. 
The limit magnitudes are below:   

UT                      Limit mag     Exp. Time
Feb. 23.52863            V  > 21.3    123 * 10
Feb. 23.52858            J  > 18.7    120 * 10
Feb. 23.52843            Ks > 16.3     96 * 10