[vsnet-grb-info 8420] GRB090926A: UVOT-enhanced XRT position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9936
SUBJECT: GRB090926A: UVOT-enhanced XRT position
DATE:    09/09/27 00:26:28 GMT
FROM:    Loredana Vetere at PSU  <vetere at astro.psu.edu>

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

Using 3190 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 =353.40070, -66.32390 which is equivalent to:

RA (J2000):  23 33 36.18
Dec (J2000): -66 19 25.9

with an uncertainty of 1.5 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.