GCN Circular 39940
Subject
GRB 250330A: Prompt Swift-XRT position
Date
2025-03-30T09:00:27Z (5 days ago)
From
K.L. Page at U Leicester <klp5@leicester.ac.uk>
Via
email
K.L. Page and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT
team:
Because of the location of Swift with respect to the South Atlantic
Anomaly at the time of the burst, XRT began collecting Photon Counting
mode data for GRB 250330A (GCN Circ. 39938) around 4 ks after the trigger.
Using promptly downlinked data we find an uncatalogued X-ray source
located at RA, Dec = 252.9515, -86.87972 which is equivalent to
RA (J2000): 16h 51m 48.36s
Dec (J2000): -86d 52' 47.0"
with an uncertainty of 3.9 arcsec (radius, 90% confidence). This is 47
arcseconds from the BAT position, inside the BAT error circle.
This circular is an official product of the Swift-XRT team.