{
  "bibcode": "2021GCN.30569....1D",
  "body": "Antonino D'Ai (INAF-iASFPA), P.A. Evans and M.R. Goad (U. Leicester) report\non behalf of the Swift-XRT team:\n\nUsing 963 s of XRT Photon Counting mode data and 4 UVOT\nimages, we find an astrometrically corrected X-ray position (using the\nXRT-UVOT alignment and matching UVOT field sources to the USNO-B1\ncatalogue): RA, Dec =\n300.30500, -28.06105 which is equivalent to:\n\nRA (J2000):  20 01 13.20\nDec (J2000): -28 03 39.8\n\nwith an uncertainty of 2.6 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.",
  "circularId": 30569,
  "createdOn": 1627809881000,
  "email": "antonino.dai@inaf.it",
  "subject": "GRB210731A: Enhanced Swift-XRT position",
  "submitter": "Antonino D'Ai at IASF-PA  <antonino.dai@inaf.it>",
  "eventId": "GRB 210731A"
}