{
  "bibcode": "2017GCN.21320....1V",
  "body": "A. Volnova (IKI),  E. Mazaeva (IKI), A. Pozanenko (IKI), A. Kusakin \n(Fesenkov Astrophysical Institute),  I. Reva (Fesenkov Astrophysical \nInstitute)    report on behalf of larger GRB follow-up collaboration:\n\nWe observed the field of the Swift GRB 170705A (Starling et al. GCN \n21289) which is also detected by GBM/Fermi and Konus-Wind  (Bissaldi  et \nal., GCN 21297; Svinkin et al., GCN 21299)  with Zeiss-1000 1-m \ntelescope of Tien Shan Astronomical Observatory on July 6-8.  We took \nseveral images in R-filter.  The optical afterglow  of GRB 170705A \n(Starling et al. GCN 21289, Lipunov et al. GCN 21291, Butler et al. GCN \n21293, Emery et al. GCN 21294; Ugarte Postigo et al. GCN 21298)  is \nvisible in a combined image on July 6, and upper limit only for July \n7-8. Preliminary  photometry of the afterglow is following.\n\nDate       UT start   t-T0    Filter Exp.  OT     Err. UL\n                      (mid, days)     (s)             (3 sigma)\n\n2017-07-06 16:28:29  1.61411  R    38*180  20.67  0.24 21.1\n2017-07-07 17:30:55  2.63106  R    13*180  n/d    n/d  20.6\n2017-07-07 17:30:55  3.10501  R    34*180  n/d    n/d  21.1\n\nPhotometry is based on nearby SDSS DR9 stars listed in GCN 21300.",
  "circularId": 21320,
  "createdOn": 1499794743000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 170705A: TShAO optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 170705A"
}