[vsnet-grb-info 12462] GRB 121001A: Enhanced Swift-XRT Position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13837
SUBJECT: GRB 121001A: Enhanced Swift-XRT Position
DATE:    12/10/02 07:12:24 GMT
FROM:    Phil Evans at U of Leicester  <pae9 at leicester.ac.uk>

P.A. Evans (U. Leicester) reports on behalf of the Swift-XRT team:

Using 2340 s of XRT Photon Counting mode data and 3 UVOT images of GRB 
121001A (D'Elia et al., GCN Circ. 13831), 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 = 276.03227, -5.66587 
which is equivalent to:

RA (J2000):  18 24 07.74
Dec (J2000): -05 39 57.1

with an uncertainty of 1.8 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.