[vsnet-grb-info 15361] GRB 140709B: TShAO optical upper limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16651
SUBJECT: GRB 140709B: TShAO optical upper limit
DATE:    14/08/01 17:36:06 GMT
FROM:    Alexei Pozanenko at IKI, Moscow  <apozanen at iki.rssi.ru>

A. Volnova (IKI), W. Mundrzyjewski (Fesenkov Astrophysical Institute), 
A. Kusakin (Fesenkov Astrophysical Institute), A. Pozanenko (IKI) report 
on behalf of larger GRB follow-up collaboration:

We observed the field of the Swift GRB 140709B  (Swenson et al., GCN 
16551) with Zeiss-1000 (West) telescope of Tien Shan Astronomical 
Observatory starting on July 9, (UT) 15:50:27, i.e. 35 minutes after GRB 
trigger. We took several images in R-filter.  Within enhanced XRT error 
circle  (Goad et al., GCN 16556) we do not detect any new object in 
stacked images.

Details of a photometry of stacked images are following

Date       UT start  t-T0,d  Exp,s   Filter Up_Lim (3 sigma)

2014-07-09 15:50:27  0.09193 13*600  R      20.5
2014-07-10 15:36:01  1.06090 13*600  R      19.8

The photometry is based on SDSS star J094401.61+633253.8 assuming
R=16.010+/-0.013 (using gri -> R Lupton transformations).