[vsnet-grb-info 13221] GRB 130504A: Enhanced XRT position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14558
SUBJECT: GRB 130504A: Enhanced XRT position
DATE:    13/05/04 16:47:01 GMT
FROM:    Paolo D'Avanzo at INAF-OAB  <paolo.davanzo at brera.inaf.it>

P. D'Avanzo (INAF-OAB), P.A. Evans and M.R. Goad (U. Leicester) report on
behalf of the Swift-XRT team:

Using 3463 s of XRT Photon Counting mode data and 5 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 =
272.45604, -16.31339 which is equivalent to:

RA (J2000):  18 09 49.45
Dec (J2000): -16 18 48.2

with an uncertainty of 1.7 arcsec (radius, 90% confidence).

This position may be improved as more data are received.  The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. 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.