TITLE: GCN CIRCULAR NUMBER: 19777 SUBJECT: IceCube-160731A: Konus-Wind limits DATE: 16/08/05 15:52:16 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report: Using Konus-Wind (KW) data, we have performed a search for a gamma-ray transient around the time of the cosmic neutrino candidate IceCube- 160731A (http://gcn.gsfc.nasa.gov/notices_amon/6888376_128290.amon) No triggered KW event happened from ~5 days before to ~1 day after the IceCube event. The nearest KW triggers are GRB 160726A (Frederiks et al, GCN 19733) and GRB 160802A (Kozlova et al, GCN 19767) Using Konus-Wind waiting mode data in the interval ±1000 s around the IceCube trigger (July 31, 2016, 1:55:04 UTC), we estimate an upper limit (90% conf.) on the 20 – 1200 keV fluence to ~7.7x10^-7 erg/cm^2 for a burst with duration less than 2.944 s and with a typical KW short GRB spectrum (an exponentially cut off power law with alpha =-0.5 and Ep=500 keV, Svinkin et al. 2016). For a typical long GRB spectrum (the Band function with alpha=-1, beta=-2.5, and Ep=250 keV), the corresponding limiting peak flux is ~5.8x10^-7 erg/cm^2/s (20 – 1200 keV, 2.944 s scale). A plot of the KW waiting mode data can be found at http://www.ioffe.ru/LEA/IceCube/kw20160731_06904_bg.png All the quoted values are preliminary.