TITLE:   GCN CIRCULAR
NUMBER:  19776
SUBJECT: GRB 160804A: TSHAO optical observations
DATE:    16/08/05 15:44:31 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>

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

We observed the field of GRB 160804A  (Marshall et al., GCN 19761)  with 
Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical Observatory. 
We obtained several images in R filter starting on August 04 (UT) 
15:08:18. We clearly detected  optical source reported by Breeveld et 
al. (GCN 19764), Tyurina et al. (GCN 19768), Malesani et al. (GCN 
19770), Moskvitin et al. (GCN 19771), Xu et al. (GCN #19773) and Bolmer 
et al. (GCN 19774). Preliminary photometry of a combined image is following

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

2016-08-04 15:08:18 0.58601  R       26*120 20.30  0.10  21.4

Photometry is based on nearby SDSS DR9 stars

SDSS-DR9_id    R(Lupton)
J144642.43+100147.7    18.068
J144642.15+100017.4    17.644
J144638.04+095917.6    17.971
J144635.67+095910.6    18.378
J144632.91+100104.9    17.910
J144619.22+095958.1    16.677
J144616.60+100018.4    16.575
J144614.88+100001.4    16.544