[AAVSO-HEN] GRB070612A: MITSuME Okayama Observation

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
For an archive and more information on circulars visit:
http://lheawww.gsfc.nasa.gov/docs/gamcosray/legr/bacodine/gcn3_archive.html

TITLE:   GCN CIRCULAR
NUMBER:  6531
SUBJECT: GRB070612A: MITSuME Okayama Observation
DATE:    07/06/13 23:25:29 GMT
FROM:    Michitoshi Yoshida at Okayama Astrophysical Obs  <yoshida at oao.nao.ac.jp>

M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama (OAO, NAOJ)
and N. Kawai (Tokyo Tech) report on behalf of the MITSuME
collaboration:

We performed optical imaging observations (Rc and Ic) of the
field of GRB 070612A (Grupe et al., GCN 6509) with 50cm MITSuME
telescope at Okayama Astrophysical Observatory from UT 11:19 to
UT 11:27 on June 12 2007.

We coadded 4 CCD frames for each band. Exposure time of each
frame is 1 minute. We made flux calibration using USNO B1.0
catalg. We found a faint source at the position of the afterglow
candidate reported by Cenko et al. (GCN 6525, RA:08:05:29.6,
DEC:+37:16:15) in Ic band. The Ic magnitude was 17.1 +/- 0.3.
There was no source brigher than 16.7 magnitude in Rc band. Flux
calibration was made with three USNO-B stars around the object.

---------------------------------------------------------------
band  mid-UT          exp.time     magnitude
Rc    June 12 11:23   4 x 1 min.   > 16.7 mag (upper limit)
Ic    June 12 11:34   4 x 1 min.   17.1 mag +/- 0.3 mag
---------------------------------------------------------------