[vsnet-grb-info 6798] Swift trigger 332287 is not a GRB

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8393
SUBJECT: Swift trigger 332287 is not a GRB
DATE:    08/10/21 14:47:15 GMT
FROM:    Jay R. Cummings at NASA/GSFC/Swift  <jayc at milkyway.gsfc.nasa.gov>

J. R. Cummings (NASA/UMBC/CRESST) on behalf of the Swift team:

We have analyzed BAT event data from trigger 332287 (Lyons et al.
GCN# 8392).  We cannot improve the weak peak in the image domain
at the position of the source that was reported onboard. We see a
weak peak from Cyg X1 in an image at the trigger time, and a weak
peak in the maskweighted lightcurve at the position of Cyg X1. We
conclude that the trigger was due to a weak burst from Cyg X1 and
a chance peak in the image domain, and not from a GRB.