{
  "bibcode": "2009GCN..9891....1E",
  "body": "P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team.\n\nWith 6 ks of XRT data, and 5 UVOT images from recent data downlinks we \nhave generated an enhanced XRT position for GRB 090904A, which does not\ninclude the problematic first image and is thus reliable.\n\nThe enhanced position is RA, Dec = 100.88480, +50.20300 which is\nequivalent to:\n\nRA (J2000): 06h 43m 32.35s\nDec (J2000): +50d 12' 10.8\"\n\nwith an uncertainty of 1.6 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest\nposition can be viewed at http://www.swift.ac.uk/xrt_positions. Position\nenhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans\net al. (2009, MNRAS, 397, 1177).\n\nThis circular is an official product of the Swift-XRT team.\n\n[GCN OPS NOTE(04sep09):  Per operator's desire, the Subject-line\nwas changed from \"090404A\" to \"090904A\". F.Marshall noticed this.]",
  "circularId": 9891,
  "createdOn": 1252074525000,
  "email": "pae9@star.le.ac.uk",
  "subject": "GRB 090904A: Enhanced Swift XRT position",
  "submitter": "Phil Evans at U of Leicester  <pae9@star.le.ac.uk>",
  "eventId": "GRB 090904A"
}