[vsnet-grb-info 27010] GRB 201221D: Prompt enhanced Swift-XRT position

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29113
SUBJECT: GRB 201221D: Prompt enhanced Swift-XRT position
DATE:    20/12/21 23:32:42 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  promptly downlinked XRT event data for GRB 201221D, we find an
enhanced XRT position of the afterglow: RA, Dec: 171.0587, 42.1438
which is equivalent to:
   RA (J2000)  = 11 24 14.09
   Dec (J2000) = +42 08 37.5
with an uncertainty of 4.2 arcseconds (radius, 90% confidence).
Analysis of the promptly available data is online at
http://www.swift.ac.uk/sper/1014037.

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.