{
  "bibcode": "2021GCN.31066....1M",
  "body": "A. S. Moskvitin and O. I. Spiridonova (SAO RAS),\non behalf of the GRB follow-up team report:\n\nWe observed the field of GRB 211023A (Fermi GBM team, GCN 30958,\nDi Lalla et al. GCN 30961, Lesage et al. GCN 30965, Ursi et al.\nGCN 30969, Poolakkil GCN 30998, Ridnaia et al., GCN 31022)\nwith the SAO RAS 1-m telescope Zeiss-1000 + CCD-photometer\non November 9. We obtained 6 x 300 sec. frames in Rc band\n(00:25:41 -- 01:31:04 UT, T_mid-T0 = 16.4949 days) and 6 x 300 sec.\nframes in Ic (00:31:28 -- 01:36:45 UT, T_mid-T0 = 16.4989 days).\n\nThe afterglow (Zhirkov et al. GCN 30977, Kann et al. GCN 30982,\nHu et al.GCN 30990, Belkin et al. GCN 31004, Vinko et al. GCN 31008,\nBelkin et al. GCN 31018, Belkin et al.  GCN 31020, Amit Kumar et al.\nGCN 31023, Rahul Gupta et al. GCN 31041, Strobl et al. GCN 31042,\nPozanenko et al. GCN 31053) is clearly detected in our stacked frames\nwith the following brightness: R = 21.69 +/- 0.09, I = 21.27 +/- 0.14\n(the preliminary photometry is based on nearby stars of PS1 catalogue,\ngri -> R and I by Lupton 2005 transformations).",
  "circularId": 31066,
  "createdOn": 1636479148000,
  "email": "mosk@sao.ru",
  "subject": "GRB 211023A: SAO RAS optical observations",
  "submitter": "Moskvitin Alexander at SAO RAS  <mosk@sao.ru>",
  "eventId": "GRB 211023A"
}