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GCN Circular 21476

LIGO/Virgo G297595: SPI-ACS/INTEGRAL data investigations
2017-08-14T14:39:09Z (7 years ago)
Alexei Pozanenko at IKI,Moscow <>
A. Pozanenko (IKI), P. Minaev (IKI),
   E. Mazaeva (IKI), A. Volnova (IKI) report  on behalf of IKI-GW 
follow-up collaboration:

We investigated  data of SPI-ACS/INTEGRAL data around LIGO/Virgo trigger 
#G297595 (LIGO/Virgo collaboration). The small peak with duration of 
about 10 seconds starting 1.5 seconds before the time of the trigger 
2017-08-14 (UTC) 10:30:43 is detected. Significance of the peak is 3.5 
sigma and the significance is estimated using local background 
dispersion +/- 2000 seconds around the peak. The center of the 
LIGO/Virgo trigger localization (R.A.=02h44m  Dec.-45d29m ) is  off-axis 
of SPI detector of 78 degrees, which is nearly optimal for maximum 
sensitivity of the SPI-ACS detector. The fluence of the peak can be 
estimated as (4.0 +/- 1.2)*10^-7 erg/��m2. While the more accurate two 
parameter chance probability will be estimated we  note  that within 
investigated interval +/- 2000 s around the LIGO/Virgo trigger we do not 
find any more significant peak with the duration of 10 seconds.

The light curve of the peak can be found at
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