GCN Circular 203
Subject
GRB990123, BeppoSAX-NFI X-ray afterglow detection
Date
1999-01-23T18:47:56Z (25 years ago)
From
Luigi Piro at IAS/CNR Frascati <piro@alpha1.ias.rm.cnr.it>
Luigi Piro on behalf of the BeppoSAX team report:
A BeppoSAX follow-up of GRB990123 initiated around 15:40 UT,
i.e. 6 hr after the burst. Preliminary analysis of the first 20 minutes
of the data at SOC shows a previously unknown strong source
(about 10**-11 c.g.s in the 1.6-10 keV) in the center of the WFC error circle.
Preliminary coordinates are:
R.A.(2000)= 231.374
DEC(2000)= +44.758
The error radius is 1.5'.
Considering its strenght, this X-ray source is very likely the X-ray
afterglow of GB990123. We will continue to observe it to monitor
its temporal evolution.