GCN Circular 9965
Subject
Correction: GRB 090929B: Enhanced Swift-XRT position
Date
2009-09-29T14:09:34Z (15 years ago)
From
Kim Page at U.of Leicester <kpa@star.le.ac.uk>
K.L. Page (U. Leicester) reports on behalf of the Swift-XRT team:
GCN Circ. 9964 referred to GRB 090929 when, in fact, the position given
is for GRB 090929B (GCN Circ. 9963). The correct text should read
Using 2438 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 090929B, 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 = 117.72015, -0.65764 which is
equivalent
to:
RA (J2000): 07h 50m 52.84s
Dec (J2000): -00d 39' 27.5"
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).
We apologise for any confusion.