GCN Circular 38034
Subject
EP241021a: Upper limit from Konus-Wind observations
Date
2024-11-01T13:52:02Z (2 months ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
Via
Web form
D. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
Konus-Wind (KW) was observing the whole sky at the time of the
detection of a fast X-ray transient EP241021a (2024-10-21 05:07:56 UTC,
hereafter T0; Hu et al., GCN 37834).
Using waiting-mode data within the interval T0 +/- 1000 s,
we found no significant (> 5 sigma) excess over the background
in S1 KW detector, with smallest incident angle,
on temporal scales from 2.944 s to 1000 s.
We estimate an upper limit (90% conf.) on the 20 - 1500 keV peak flux
to 2.5x10^-7 erg/cm^2/s for a typical long GRB spectrum
(the Band function with alpha=-1, beta=-2.5, and Ep=300 keV) and 2.944 s timescale.
All the quoted values are preliminary.