[vsnet-grb-info 17893] GRB 160424A - XRT position uncertain

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19339
SUBJECT: GRB 160424A - XRT position uncertain
DATE:    16/04/25 07:49:42 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:

During the XRT observations of GRB 160424A (Evans et al., GCN Circ. 
19336) the star trackers onboard Swift were unable to acquire a correct 
lock. As a result of this the attitude solution for the spacecraft is 
uncertain, and visual inspection of the images shows that the position 
of the XRT afterglow is highly uncertain. Our best estimate of the 
position is as given in GCN Circ. 19336, however the uncertainty is  ~50 
arc sec.

This circular is an official product of the Swift-XRT team.