TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3640 SUBJECT: Konus-Wind observation of GRB 050717 DATE: 05/07/18 14:22:55 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report: The long hard GRB 050717 (Swift-BAT trigger #146372; Hurkett et al., GCN 3633, 3636) triggered Konus-Wind at T0=37857.426s UT (10:30:57.426). As observed by Konus-Wind it had a steep rise and a long decaying tail. This tail is seen up to ~50 s after T0. The burst fluence is ~6.0x10-5 erg/cm2, peak flux on 64-ms time scale is ~1.2x10-5 erg/cm2 s (both in the 20 keV - 6 MeV energy range). The uncertainties in the derived fluence and peak flux are dominated by uncertainties in high energy part of the GRB's spectra (the fluence calculated in 20-350 keV energy range is 1.2x10-5 erg/cm2, which coincides with the value derived by Swift-BAT) The time-integrated spectrum (from T0 to T0+51.712 s) is well fitted (in 20 keV-6 MeV range) by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) exp(-E/E0) with alpha = 1.12 (-0.17, +0.13), and E0 = 2150 (-1070, +2300) keV. The peak energy Ep = 1890 (-760, +1600) keV. The spectrum can also be fitted by a GRBM (Band) model, but in this case the high energy photon index beta = -1.71 (-0.95, +0.21) and only lower limit on Ep can be found: Ep >= 900 keV. The spectrum of the main peak (from T0 to T0+5.376 s) is well fitted (in 20 keV-6 MeV range) by a power law with exponential cutoff model with alpha = 1.06 ± 0.10, and E0 = 2470 (-850, +1480) keV. The peak energy Ep = 2300 (-670, +1100) keV. (For GRBM model, beta = -1.73 (-0.33, +0.21)). All quoted unceratinties are at 90% confidence level.