{
  "eventId": "GRB 241223A",
  "bibcode": "2024GCN.38671....1S",
  "submitter": "Phil Evans at U of Leicester <pae9@star.le.ac.uk>",
  "body": "B. Sbarufatti (INAF-OAB), C. Salvaggio (INAF-OAB), S. Dichiara (PSU),\nJ.A. Kennea (PSU), D.N. Burrows (PSU), K.L. Page (U. Leicester), A.P.\nBeardmore (U. Leicester), M. Ferro (INAF-OAB) and P.A. Evans (U.\nLeicester) reports on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/GBM-detected burst GRB 241223A, collecting  2.2 ks of Photon\nCounting (PC) mode data between T0+20.5 ks and T0+99.8 ks. \n\nNo X-ray sources have been detected at the position of the GOTO optical\nsource (GCN Circ. 38655). The 3-sigma upper limit in the field ranges\nfrom ~0.005 to ~0.006 ct s^-1, corresponding to a 0.3-10 keV observed\nflux of 2.0e-13 to 2.5e-13 erg cm^-2 s^-1 (assuming a typical GRB\nspectrum).\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021749.\n\nThis circular is an official product of the Swift-XRT team.\n\n",
  "subject": "GRB 241223A: Swift-XRT observations",
  "submittedHow": "email",
  "circularId": 38671,
  "createdOn": 1735144930241
}