{
  "bibcode": "2005GCN..3976....1P",
  "body": "K. Page (U. Leicester), D. Burrows (PSU), N. Gehrels (GSFC), P. O'Brien\n(U. Leicester), F. Marshall (GSFC) and P. Boyd (GSFC-UMBC) report on\nbehalf of the Swift-XRT team:\n\nUpon analysis of 29 ks of data, starting 4.6 hours after the BAT detected\nGRB050911 (trigger number 154630; GCN 3961), no fading X-ray source is\nfound within the BAT refined error circle (GCN 3964; Tueller et al.) The\nsource suggested in GCN 3967 (Page et al.) is found to constant over time,\nso is not believed to be the afterglow.\n\nWe place a 3 sigma upper limit of 6.7e-4 count s^-1 on the count-rate,\nwhich corresponds to an unabsorbed flux of 2.8e-14 erg cm^-2 s^-1 (over\n0.3-10 keV), assuming a Crab-like spectrum. Since this GRB looks like a\nreal burst in the BAT data, we conclude that it must have had a\nrapidly-decaying X-ray afterglow to have faded below the XRT sensitivity\nin 4.6 hours.",
  "circularId": 3976,
  "createdOn": 1126768434000,
  "email": "kpa@star.le.ac.uk",
  "subject": "GRB050911: Upper limit on X-ray afterglow",
  "submitter": "Kim Page at U.of Leicester  <kpa@star.le.ac.uk>",
  "eventId": "GRB 050911"
}