GCN Circular 21320
Subject
GRB 170705A: TShAO optical observations
Date
2017-07-11T17:39:03Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), E. Mazaeva (IKI), A. Pozanenko (IKI), A. Kusakin
(Fesenkov Astrophysical Institute), I. Reva (Fesenkov Astrophysical
Institute) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 170705A (Starling et al. GCN
21289) which is also detected by GBM/Fermi and Konus-Wind (Bissaldi et
al., GCN 21297; Svinkin et al., GCN 21299) with Zeiss-1000 1-m
telescope of Tien Shan Astronomical Observatory on July 6-8. We took
several images in R-filter. The optical afterglow of GRB 170705A
(Starling et al. GCN 21289, Lipunov et al. GCN 21291, Butler et al. GCN
21293, Emery et al. GCN 21294; Ugarte Postigo et al. GCN 21298) is
visible in a combined image on July 6, and upper limit only for July
7-8. Preliminary photometry of the afterglow is following.
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s) (3 sigma)
2017-07-06 16:28:29 1.61411 R 38*180 20.67 0.24 21.1
2017-07-07 17:30:55 2.63106 R 13*180 n/d n/d 20.6
2017-07-07 17:30:55 3.10501 R 34*180 n/d n/d 21.1
Photometry is based on nearby SDSS DR9 stars listed in GCN 21300.