GCN Circular 21746

D. Svinkin, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, 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 G298048 (2017-08-17 12:41:04.446 UTC, hereafter T0; 
LIGO/Virgo Collaboration GCN Circ. 21509
Not found
 
 
) coincident with Fermi GBM 
trigger 524666471 (Connaughton et al., GCN Circ. 21506
Not found
 
 
, Goldstein et 
al., GCN Circ. 21528
Not found
 
 
).

Using waiting-mode data within the interval T0 +/- 100 s,
we found no significant (> 4 sigma) excess over the background
in both KW detectors on temporal scales from 2.944 s to 100 s.

For the 2.944 s interval containing GBM trigger and the 
highest-probability localization region for the LIGO/Virgo G298048 (LVC, 
GCN Circ. 21513
Not found
 
 
) we estimate an upper limit (90% conf.) on the 10 keV ��� 
10 MeV fluence to 3.0x10^-7 erg/cm^2 for a burst lasting less than 2.944 
s and having the spectrum reported by Goldstein et al. (an exponentially 
cut off power law, CPL, with alpha=-0.9 and Ep=128 keV).
For a typical short GRB spectrum (CPL with alpha=-0.5 and Ep=500 keV), 
the limiting fluence is 6.9x10^-7 erg/cm^2 (10 keV ��� 10 MeV).

All the quoted values are preliminary.