TITLE: GCN CIRCULAR NUMBER: 20629 SUBJECT: Konus-Wind observation of GRB 170207A DATE: 17/02/08 17:11:32 GMT FROM: Dmitry Svinkin at Ioffe Institute 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: The long-duration, very bright GRB 170207A (IPN triangulation: Svinkin et al, GCN Circ. 20628) triggered Konus-Wind at T0=78301.73 s UT (21:45:01.730). The burst light curve shows three multipeaked emission episodes which started at ~T0-0.3 s and had a total duration of ~42 s. The emission is seen up to ~10 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB170207_T78301/ As observed by Konus-Wind, the burst had a fluence of 7.84(-0.96,+0.85)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+18.016 s, of 1.50(-0.21,+0.26)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+41.984 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.86(-0.06,+0.06), the high energy photon index beta = -2.63(-0.84,+0.26), the peak energy Ep = 394(-33,+42) keV (chi2 = 106/97 dof) The spectrum near the maximum count rate (measured from T0+13.824 to T0+18.944 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.63(-0.08,+0.08), the high energy photon index beta = -3.60(-6.40,+0.83), the peak energy Ep = 524(-46,+56) keV (chi2 = 107/82 dof) All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.