GCN Circular 26849
Subject
LIGO/Virgo S200115j: Upper limits from Konus-Wind observations
Date
2020-01-22T07:28:50Z (5 years ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
A. Ridnaia, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline,
on behalf of the Konus-Wind team, report:
Konus-Wind (KW) was observing the whole sky at the time of the
LIGO/Virgo event S200115j (2020-01-15 04:23:09.742 UTC, hereafter T0;
LIGO/Virgo Collaboration GCN Circ. 26759).
No triggered KW GRBs happened ~1 day before and ~17 hours
after T0. The closest waiting-mode GRB was observed ~3 hours after T0.
Using waiting-mode data within the interval T0 +/- 100 s,
we found no significant (> 5 sigma) excess over the background
in both KW detectors on temporal scales from 2.944 s to 100 s.
We estimate an upper limit (90% conf.) on the 20 - 1500 keV fluence
to 9.3x10^-7 erg/cm^2 for a burst lasting less than 2.944 s and having a
typical KW short GRB spectrum (an exponentially cut off power law with
alpha =-0.5 and Ep=500 keV). For a typical long GRB spectrum (the Band
function with alpha=-1, beta=-2.5, and Ep=300 keV), the corresponding
limiting peak flux is 2.8x10^-7 erg/cm^2/s (20 - 1500 keV, 2.944 s scale).
All the quoted values are preliminary.