TITLE: GCN CIRCULAR NUMBER: 33379 SUBJECT: GRB 230228A: Prompt enhanced Swift-XRT position DATE: 23/02/28 06:35:05 GMT FROM: Phil Evans at U of Leicester pae9@leicester.ac.uk

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

Using promptly downlinked XRT event data for GRB 230228A, we find an enhanced XRT position of the afterglow: RA, Dec: 18.37804, 44.48289 which is equivalent to: RA (J2000) = 01 13 30.73 Dec (J2000) = +44 28 58.4 with an uncertainty of 1.9 arcseconds (radius, 90% confidence). Analysis of the promptly available data is online at http://www.swift.ac.uk/sper/1156572.

Position enhancement is 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.