{
  "bibcode": "2019GCN.23661....1B",
  "body": "S. Belkin (IKI),  A. Pozanenko (IKI), P. Minaev (IKI), E. Klunko (ISTP), \nI. Reva (FAPI), M. Krugov (FAPI), V. Rumyantsev (CrAO), R. Ya. \nInasaridze (AbAO), E. Mazaeva (IKI), A. Volnova (IKI)   report   on \nbehalf of IKI-FuN:\n\nWe continue observations the optical afterglow (e.g. Lipunov  et al. \nGCN 23616, Itoh et al. GCN 23617, Mao et al. GCN 23618, Reva et al., GCN \n23620, Xin et al. GCN 23622, Quadri et al. GCN 23624, Hu et al. GCN \n23627)  of  the GRB 190106A (Sonbas et al., GCN 23615)  with AZT-33IK \ntelescope of Sayan observatory (Mondy), Zeiss-1000 1-m telescope of Tien \nShan Astronomical Observatory, and  AS-32 (0.7m) telescope of Abastumani \nObservatory.  Preliminary photometry of the afterglow is following.\n\nDate       UT start t-T0    Filter Exp.   OT    Err. Observatory\n                    (mid, days) (s)\n\n2019-01-07 17:27:12 1.19251 R      63*60  20.27 0.08  AbAO\n2019-01-08 11:07:16 1.91774 R      30*120 21.11 0.13  Mondy\n2019-01-08 15:53:23 2.09628 R      12*120 21.1  0.3   CrAO\n\n\nThe photometry is based on nearby SDSS  stars\nSDSS-DR12_id              R(Lupton)\nJ015920.22+235150.7 16.475\nJ015929.35+235237.5 15.774\n\nBased on our previous results (GCNs 23620, 23638, 23640) and photometry \nabove we plot a light curve  ( \nhttp://grb.rssi.ru/GRB190106A/GRB190106A_LC_R_fit.png ). We could \nsuggest the jet break at 1.5 +/- 0.5 days.",
  "circularId": 23661,
  "createdOn": 1547059335000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 190106A: optical observations, possible jet break detection",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 190106A"
}