[vsnet-grb-info 9503] GRB 100724A: Enhanced Swift-XRT position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10974
SUBJECT: GRB 100724A: Enhanced Swift-XRT position
DATE:    10/07/24 16:03:15 GMT
FROM:    Phil Evans at U of Leicester  <pae9 at star.le.ac.uk>

A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 6782 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 100724A, 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 = 194.54312, -11.10263 which is equivalent
to:

RA (J2000): 12h 58m 10.35s
Dec (J2000): -11d 06' 09.5"

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 was automatically generated, and is an official product of the
Swift-XRT team.