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GCN Circular 9988

GRB 091003: UVOT-enhanced XRT position
2009-10-04T12:10:23Z (15 years ago)
Rhaana Starling at U of Leicester <>
R.L.C. Starling, P.A. Evans, A.P. Beardmore and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team:

Using 4881 s of XRT Photon Counting mode data and 11 UVOT 
images for GRB 091003, 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 =
251.51980, 36.62470 which is equivalent to:

RA (J2000):  16 46 4.75
Dec (J2000): +36 37 29.0

with an uncertainty of 1.7 arcsec (radius, 90% confidence). The UV 
counterpart reported in Gronwall & Starling (GCN Circ.9987) is consistent 
with this position.

This position may be improved as more data are received.  The latest
position can be viewed at 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.
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