{
  "bibcode": "2024GCN.38709....1V",
  "submitter": "Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com>",
  "body": " A. Volnova (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov (HSE)\nreport on behalf of GRB IKI FuN:\n\nWe observed the field of GRB 241228B triggered by Fermi (Fermi GBM team,\nGCN 38682) with AZT-33IK telescope of Mondy observatory in R-filter\nstarting on (UT) 2024-12-28 19:42:31. We clearly detect optical afterglow\n(Kumar et al., GCN 38684 and GCN 38691; An et al. GCN 38687; Ortega-Casas\net al., GCN 38692; Ghosh et al., GCN 38702; An et al., GCN 38704).\nPreliminary photometry of the afterglow is the following\n\nDate UT start t-T0 Exp. Filter OT Err. UL(3sigma)\n(mid, days) (s)\n2024-12-28 19:42:31 0.66628 30x120 R 20.28 0.04 23.0\n\nThe photometry is based on nearby SDSS DR16 stars (R mags by Lupton\ntransformation).\n",
  "submittedHow": "email",
  "eventId": "GRB 241228A",
  "createdOn": 1735490588533,
  "circularId": 38709,
  "subject": "GRB 241228A: Mondy optical afterglow observations"
}