[vsnet-grb-info 19038] GRB 170202A: Kanata optical and infrared observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  20581
SUBJECT: GRB 170202A: Kanata optical and infrared observations
DATE:    17/02/02 23:12:08 GMT
FROM:    Michitoshi Yoshida at HASC,Hiroshima U  <yoshidam at hiroshima-u.ac.jp>

Mori, H., Nakaoka, T., Kawabata, M., Hirochi, J., Kawahara, N.,
Yoshida, M., Kawabata, K. and Uemura, M. (Hiroshima Univ.) on
behalf of the OISTER collaboration

We performed R-band and Ks-band imaging observations around the
error circle of GRB 170202A (Racusin et al., GCN 20575) with the
optical imager HOWPol and opt-NIR imager HONIR attached to Kanata
telescope of Hiroshima University. The observations took place at
2017-02-02 18:33:37 UT (mid time of the observation). We detected
the optical transient reported by Xin et al.(GCN 20576), Lipunov
et al. (GCN 20578) and Guidorzi et al. (GCN 20579) in our R-band
and Ks-band images. The detected magnitude of the OT and five
sigma upper limit (in Vega magnitude) of the observations are
listed below.

# T0+   MID-UT     T-EXP    R mag.   R err   R limit
-----------------------------------------------------
  335    18:33:37      30    16.35    0.3     18.0
-----------------------------------------------------

# T0+   MID-UT     T-EXP    Ks mag.  Ks err  Ks limit
-----------------------------------------------------
  3208   19:21:30    1320    17.1     0.4     18.6
-----------------------------------------------------
T0+ : Elapsed time after the burst [sec]
T-EXP: Total Exposure time [sec]