{
  "bibcode": "2009GCN..9860....1C",
  "body": "J.R. Cummings (NASA/UMBC), P.A. Evans (U. Leicester), J.A. Kennea (PSU), \nC. Pagani (PSU), and M. De Pasquale (MSSL/UCL) on behalf of the Swift \nteam report:\n\nThe ground analysis of BAT data from trigger 361477 (De Pasquale et al., \nGCN Circ. 9851) shows a very weak excess in the low energy bands only. \nThe response is consistent with a somewhat unusually large noise \nfluctuation in the image domain caused by the presence of a bright source \nin the BAT partially coded field of view (Cyg-X1).\n\nThe XRT observed the field for 3.23 ks between T0+150 s and T0+10 ks. The \ndata are entirely in Photon Counting mode. We do not find any source in \nthe field of view. A 3-sigma upper limit on covering the BAT onboard error \ncircle is 2.7 x 10^-3 ct/sec.\n\n  No new source is found in the UVOT white filter finding chart (153-303s \nafter the trigger) inside the BAT error circle down to a 3 sigma upper \nlimit of 20.9.\n\n  We conclude that the trigger is unlikely to be due to a GRB or any other \nastrophysical source.",
  "circularId": 9860,
  "createdOn": 1251809104000,
  "email": "mdp@mssl.ucl.ac.uk",
  "subject": "Swift Trigger 361477, called GRB090831B, is probably not real.",
  "submitter": "Massimiliano de Pasquale at MSSL-UCL  <mdp@mssl.ucl.ac.uk>",
  "eventId": "GRB 090831B"
}