{
  "circularId": 46102,
  "eventId": "GRB 261029A",
  "format": "text/plain",
  "eventType": [
    "GRB",
    "Optical Transient"
  ],
  "submitter": "Filip Novotný at Masaryk University <filip.novotny@talentovani.cz>",
  "subject": "GRB 261029A: Ondrejov D50 optical observations, possible rebrightening",
  "body": "F. Novotny, J. Strobl, M. Jelinek and R. Hudec (ASU CAS Ondrejov) report:\n\nWe observed the field of GRB 261029A (Fermi GBM team, GCN 46071;\nGoto et al., GCN 46072) with the D50 robotic telescope of the\nAstronomical Institute Ondrejov, near Prague, Czech Republic.\nWe obtained a long series of 60s Sloan i'-band exposures between\nstarting at 16:42UT on 2026 October 29 (T0+15.3h or 0.64d);\nobservations are continuing.\n\nThe photometry of combined images (15x60s) suggests there has been a\nrebrightening or a flat phase, and that the afterglow reached i~19.6 \nat 0.75 day post-burst, at which point it starts to be compatible with a\ndecay again.\n\nPhotometry is calibrated in Sloan i' (AB system) against\nATLAS-RefCat2 field stars, not corrected for Galactic extinction\n(E(B-V)=0.081 mag).",
  "createdOn": 1793316031218,
  "submittedHow": "web"
}