{
  "bibcode": "2017GCN.21001....1M",
  "body": "A. Moskvitin (SAO RAS),  E. Mazaeva (IKI), A. Pozanenko (IKI),\nA. Volnova (IKI), on behalf of larger GRB follow-up collaboration:\n\n\nWe observed the field of GRB 170317A (LaPorte et al. GCN 20885)\nwith the SAO RAS telescope Zeiss-1000  + CCD photometer on March, 17\n(18:12:00--19:58:03 UT). We obtained several images in Rc band.\nThe optical afterglow (LaPorte et al., GCN 20885;\nMazaeva et al., GCN 20886; Xin et al., GCN 20888;\nMao et al., GCN 20889; Kuroda et al., GCN 20899) is detected\nin a stacked frame. Preliminary photometry is following\n\nDate       UT start   t-T0        Filter  Exp.   OT     Err. UL\n                      (mid, days)         (s)\n\n2017-03-17 18:12:00   0.38823     Rc     15*300  22.3   0.3  22.6\n\nPhotometry is based on nearby USNO-B1.0 stars\npreviously used in GCN 20886.",
  "circularId": 21001,
  "createdOn": 1491596622000,
  "email": "mosk@sao.ru",
  "subject": "GRB 170317A: SAO RAS optical observations",
  "submitter": "Moskvitin Alexander at SAO RAS  <mosk@sao.ru>",
  "eventId": "GRB 170317A"
}