[vsnet-grb-info 8028] GRB 090621A: Enhanced Swift-XRT position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9567
SUBJECT: GRB 090621A: Enhanced Swift-XRT position
DATE:    09/06/24 09:24:00 GMT
FROM:    Kim Page at U.of Leicester  <kpa at star.le.ac.uk>

K.L. Page, P.A. Evans and M.R. Goad (U. Leicester) report
on behalf of the Swift-XRT team:

Using 5877 s of XRT Photon Counting mode data and 11 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 = 11.02150, 61.94110 which is equivalent to:

RA (J2000):  00 44 5.16
Dec (J2000): +61 56 28.0

with an uncertainty of 1.4 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, arXiv:0812.3662).

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