{
  "bibcode": "2021GCN.29265....1K",
  "body": "V. Kim (FAI, Pulkovo Observatory), A. Pozanenko (IKI),  M. Krugov (FAI), \nS. Belkin (IKI), Y. Aimuratov (FAI) report on behalf of GRB IKI FuN:\n\nWe continued observations of the GRB 210104A (Fermi GBM team, GCN 29232; \nTroja et al., GCN  29233; Frederiks et al., GCN  29258) with AZT-20 \ntelescope of Assy-Turgen observatory starting on  Jan. 05 (UT) 12:55:33 \nin r'-filter.  We detect the optical afterglow (Troja et al., GCN \n29233; Xin et al., GCN 29235; Hu et al., GCN 29236; Hosokawa et al., GCN \n  29237; Kim et al., GCN 29238; Lipunov et al., GCN 29239; Horiuchi et \nal., GCN 29241; Breeveld et al., GCN 29247; Zhu et al., GCN 29252; Paek \n  et al., GCN 29254; Kumar et al., GCN 29257; Smartt et al., GCN 29262).\n\nPreliminary photometry obtained in images in the beginning of \nobservations on Jan. 05 is following\n\nDate       UT start     Filter  Exp.    OT    Err.\n                                 (s)\n\n2021-01-04 15:35:27     r'(AB)  20*60   20.85 0.07\n2021-01-04 16:20:20     r'(AB)  20*60   21.23 0.10\n2021-01-04 17:05:11     r'(AB)  20*60   21.19 0.06\n\nThe photometry is based on nearby stars of PanSTARRS-PS1.\nObservations are continuing.",
  "circularId": 29265,
  "createdOn": 1609884722000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 210104A: Assy continued optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 210104A"
}