{
  "bibcode": "2008GCN..7755....1G",
  "body": "M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) \nreport on behalf of the Swift-XRT team.\n\nUsing 497 s of overlapping XRT Photon Counting mode and UVOT\ndata for GRB 080520, we find an astrometrically corrected X-ray\nposition (using the XRT-UVOT alignment and matching UVOT field sources\nto the USNO-B1 catalogue): RA, Dec = 280.19385, -54.99160 which is equivalent\nto:\n\nRA (J2000): 18h 40m 46.52s\nDec (J2000): -54d 59' 29.8\"\n\nwith an uncertainty of 1.9 arcsec (radius, 90% confidence).\n\nThis position may be improved as more data are received. The latest position\ncan be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is\ndescribed by Goad et al. (2007, A&A, 476, 1401\nhttp://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an\nextension of this method.\n\nThis circular was automatically generated, and is an official product of the\nSwift-XRT team.",
  "circularId": 7755,
  "createdOn": 1211344363000,
  "email": "pae9@star.le.ac.uk",
  "subject": "GRB 080520: Enhanced Swift-XRT position",
  "submitter": "Phil Evans at U of Leicester  <pae9@star.le.ac.uk>",
  "eventId": "GRB 080520"
}