{
  "bibcode": "2017GCN.20516....1M",
  "body": "E. Mazaeva (IKI), A. Pozanenko (IKI), R. Inasaridze (AbAO), A. Volnova \n(IKI),  V. Ayvazian  (AbAO),  O.Kvaratskhelia (AbAO), G. Inasaridze (AbAO), \nI. Molotov (KIAM), report on behalf of larger GRB follow-up collaboration:\n\nWe observed the field of optical transient reported by Lipunov et al. (GCN \n20502) as a possible candidate of the Fermi/GBM GRB 170121B (Hamburg et al. \nGCN Circ. 20505) and XRT  afterglow  candidate reported by Sbarufatti  et \nal. (GCN  20510) with AS-32 (0.7m) telescope of Abastumani Observatory \nstarting on Jan., 23 (UT)  16:14:49. We obtained several unfiltered images \nof the field.  We do not find any source at coordinates of the optical \ntransient (Lipunov et al., GCN  20502). Within XRT error circle  (Sbarufatti \net al., GCN  20510) we find the source which is also presented in DSS2 and \nUSNO-B1.0 as the star USNO-B1.0 0807-0048671 (magnitudes R1 = 17.94, R2 = \n17.07). Preliminary photometry  of the source and the field of  the optical \ntransient (Lipunov et al., GCN  20502) is following\n\nDate        UT start   t-T0      Filter Exp.   OT    Err UpLim (3 sigma)\n                       (mid, days)       (s)\n\n2017-01-23 16:14:49.   2.09866   CR     60*60  17.76  0.07  22.9\n\nPhotometry is based on nearby USNO-B1.0 stars (R2 magnitudes)\nUSNO-B.1_id    R2\n0807-0048576 16.37\n0806-0049543 18.47\n0807-0048525 17.28\n0807-0048536 17.23\n0806-0049637 15.57\n0807-0048826 15.71\n0807-0048833 15.41\n0807-0048816 17.22",
  "circularId": 20516,
  "createdOn": 1485279663000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 170121B:  AbAO optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 170121B"
}