[vsnet-grb-info 20825] GRB 180706A: TSHAO optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22923
SUBJECT: GRB 180706A: TSHAO optical observations
DATE:    18/07/06 21:15:30 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

A. Volnova (IKI), I. Reva (FAPHI), E. Mazaeva (IKI), A. Pozanenko (IKI), 
  A. Kusakin (FAPHI),  M. Krugov (FAPHI) report on behalf of larger GRB 
follow-up collaboration:

We observed the field of GRB 180706A  (Stamatikos et al., GCN 22909) 
with Zeiss-1000 telescope of Tien Shan Astronomical Observatory starting 
on July 06 (UT) 16:18:35. We obtained several images in R-filter.  The 
optical afterglow (Stamatikos et al., GCN 22909;  Watson et al., GCN 
22910)  is clearly detected in a combined image.  Preliminary photometry 
of the afterglow is following.

Date        UT start t-T0     Filter Exp.    OT    Err.   UL
                      (mid, days)     (s)

2018-07-06  16:18:35 0.35345  R      29*120  20.65 0.09   22.2

The photometry is based on several SDSS-DR12 stars.

Ref.stars
SDSS-DR12_id          	R(Lupton)
J120642.39+660133.6	18.5600.025
J120649.22+660218.2	17.5190.018
J120653.24+660249.5	17.9870.017