TITLE: GCN CIRCULAR NUMBER: 41304 SUBJECT: GRB 250809A: Prompt enhanced Swift-XRT position DATE: 25/08/09 17:25:56 GMT FROM: Phil Evans at U of Leicester pae9@star.le.ac.uk

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

Using 923 s of promptly downlinked XRT event data for GRB 250809A, we find an enhanced XRT position of the afterglow: RA, Dec: 233.00043, -53.29626 which is equivalent to: RA (J2000) = 15 32 00.10 Dec (J2000) = -53 17 46.5 with an uncertainty of 3.0 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1340954.

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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