{
  "bibcode": "2021GCN.29417....1B",
  "body": "S. Belkin (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), R. Ya. Inasaridze \n(AbAO), N. Pankov (HSE) report  on behalf of GRB IKI FuN:\n\nWe observed the ZTF21aagwbjr/AT2021buv transient (Kool  et al., GCN \n29405) at  the redshift of 1.466 (Izzo et al., GCN 29411) which is most \nprobably is an afterglow (Kennea et al., GCN 29413; Teja  et al., GCN \n29414) of  GRB 210204A (Fermi GBM team, GCN 29390; Li et al., GCN 29392; \nHurley et al., GCN 29408; Waratkar et al., GCN 29410;  Frederiks et al., \nGCN 29415). Images in R-filter were taken in AZT-33IK telescope of Sayan \nobservatory (Mondy) and AS-32 telescope of Abastumani observatory (AbAO).\n\nPreliminary photometry of the optical transient in a combined image is \nfollowing\n\nDate       UT start  t-T0     Filter Exp.  OT    Err.  UL(3s) Telescope\n                      (mid, days)        (s)\n\n2021-02-06 12:33:10  2.26579  R      38*60 19.94 0.09  21.7  AZT-33IK\n2021-02-06 16:50:17  2.44748  R      47*60 20.1  0.4   20.1  AS-32\n\nThe photometry is based on the nearby USNO-B1.0 stars.\nUSNO-B1.0_id R2\n1014-0149033 15.43\n1014-0149115 17.00",
  "circularId": 29417,
  "createdOn": 1612715653000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 210204A (ZTF21aagwbjr/AT2021buv): Mondy and AbAO optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 210204A"
}