TITLE: GCN CIRCULAR NUMBER: 21442 SUBJECT: Konus-Wind observation of GRB 170805B DATE: 17/08/10 11:41:06 GMT FROM: Anna Kozlova at Ioffe Institute A.Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline on behalf of the Konus-Wind team, report: The short-duration GRB 170805B (IPN triangulation: Hurley et al., GCN 21428) triggered Konus-Wind at T0=51527.165 s UT (14:18:47.165). The burst light curve shows a single pulse which starts at T0-32 ms and has a total duration of ~0.2 s. As observed by Konus-Wind, the burst had a fluence of 1.23(-0.21,+0.46)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0-0.008 s, of 2.25(-0.47,+0.89)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). Since the most intense part of the burst was detected before the trigger, the spectral analysis was performed using the KW 3-channel light curve data. Modeling the KW 3-channel time-integrated spectrum (from T0-0.032 s to T0+0.146 s) by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields alpha = -0.97 (-0.15,+0.19), and Ep = 720 (-192,+474) keV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB170805_T51527/ All the quoted errors are at the 68% confidence level. All the quoted values are preliminary.