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GCN Circular 30569

GRB210731A: Enhanced Swift-XRT position
2021-08-01T09:24:41Z (3 years ago)
Antonino D'Ai at IASF-PA <>
Antonino D'Ai (INAF-iASFPA), P.A. Evans and M.R. Goad (U. Leicester) report
on behalf of the Swift-XRT team:

Using 963 s of XRT Photon Counting mode data and 4 UVOT
images, we find an astrometrically corrected X-ray position (using the
XRT-UVOT alignment and matching UVOT field sources to the USNO-B1
catalogue): RA, Dec =
300.30500, -28.06105 which is equivalent to:

RA (J2000):  20 01 13.20
Dec (J2000): -28 03 39.8

with an uncertainty of 2.6 arcsec (radius, 90% confidence).

This position may be improved as more data are received.  The latest
position can be viewed at Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular is an official product of the Swift-XRT team.
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