{
  "bibcode": "2021GCN.30478....1P",
  "body": "N. Pankov (HSE, IKI), M. Krugov (FAI), A. Pozanenko (IKI),  V. Kim (FAI, \nPulkovo Observatory), S. Belkin (IKI) report on behalf of GRB IKI FuN:\n\nWe observed the field of  GRB 210722A  (D'Avanzo et al., GCN 30475) with \nAZT-20 telescope of Assy-Turgen observatory starting on 2021-07-22 (UT) \n21:42:07. We obtained 30 frames in r' - filter before a twilight.\n\nWe clearly detect the bright optical afterglow (D'Avanzo et al., GCN \n30475; Zhu et al., GCN 30476) in coordinates of 01:48:07.27 \n-06:20:50.00 with accuracy of 0.1 arcsec in both coordinates. The \ncoordinates are coincides with UVOT coordinates (D'Avanzo et al., GCN 30475)\n\nPreliminary photometry of the optical afterglow in the first image of 60 \ns exposure is following\n\nDate       UT start  t-T0       Exp.    Filter  OT    Err.  UL(3sigma)\n                    (mid, days)  (s)             (AB)\n\n2021-07-22 21:42:07 0.03293     1*60    r'      16.20 0.03  21.1\n\n\nThe photometry is based on the nearby PS1 stars.",
  "circularId": 30478,
  "createdOn": 1626994180000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 210722A: Assy optical detection",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 210722A"
}