{
  "eventId": "GRB 240911A",
  "createdOn": 1726207386269,
  "submittedHow": "email",
  "bibcode": "2024GCN.37483....1W",
  "circularId": 37483,
  "submitter": "Phil Evans at U of Leicester <pae9@star.le.ac.uk>",
  "body": "M. A. Williams (PSU), S. Dichiara (PSU), J.P. Osborne (U. Leicester),\nK.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), T. Sbarrato\n(INAF-OAB), P. D'Avanzo (INAF-OAB), M.G. Bernardini (INAF-OAB), J.A.\nKennea (PSU) and P.A. Evans (U. Leicester) reports on behalf of the\nSwift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nSVOM/ECLAIRs-detected burst GRB 240911A in a series of observations\ntiled on the sky. The total exposure time is 2.9 ks, distributed over 3\ntiles; the maximum exposure at a single sky location was 1.6 ks. The\ndata were collected between T0+73.0 ks and T0+79.5 ks, and are entirely\nin Photon Counting (PC) mode. \n\nTwo uncatalogued X-ray sources have been detected, however none of them\nis above the RASS limit or shows definitive signs of fading. Therefore,\nat the present time we cannot identify which, if any, is the afterglow.\nDetails of these sources are given below:\n\nSource 1:\n  RA (J2000.0):  351.4579  =  23:25:49.91\n  Dec (J2000.0): +21.3760  =  +21:22:33.6\n  Error: 13.5 arcsec (radius, 90% conf.)\n  Count-rate: (3.7 [+2.3, -1.6])e-3 ct s^-1   \n  Distance: 554 arcsec from SVOM/ECLAIRs position.\n\nSource 2:\n  RA (J2000.0):  351.5268  =  23:26:6.43\n  Dec (J2000.0): +21.2944  =  +21:17:39.8\n  Error: 8.2 arcsec (radius, 90% conf.)\n  Count-rate: (5.5 [+3.6, -2.6])e-3 ct s^-1   \n  Distance: 771 arcsec from SVOM/ECLAIRs position.\n\nThe results of the XRT-team automatic analysis of the tiled XRT\nobservations, including a position-specific upper limit calculator, are\navailable at https://www.swift.ac.uk/xrt_products/TILED_GRB00128.\n\nThis circular is an official product of the Swift-XRT team.\n\n",
  "subject": "GRB 240911A: Swift-XRT observations"
}