[vsnet-grb-info 21150] GRB 180914B : continued TSHAO optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23249
SUBJECT: GRB 180914B : continued TSHAO optical observations
DATE:    18/09/17 20:04:01 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

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

We observed the field of GRB 180914B (Ursi, et al., GCN  23226; Bissaldi 
et al., GCN 23232;  Frederiks et al., GCN 23240) with Zeiss-1000 1-m 
telescope of Tien Shan Astronomical Observatory starting on September 17 
(UT) 14:28:30.  We observed the object reported e.g. (Zheng & Filippenko 
GCN 23237; Troja et al. GCN 23238;  de Ugarte Postigo et al., GCN 23239; 
Paul & Kuin, GCN 23241). Preliminary photometry of the object is following.

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

2018-09-17 14:28:30 2.87843 R      60*60 20.53 0.07 22.2

The photometry is based on several nearby SDSS-DR9 stars
SDSS-DR9_id            R(Lupton)
J220926.80+250130.1    15.705
J220922.87+250206.0    16.156
J220929.88+250257.7    15.812
J220928.05+250309.0    17.230
J220928.90+250327.6    15.524
J220924.12+250415.7    15.485
J220920.37+250610.6    15.050
J220902.04+250312.5    15.321