TITLE: GCN CIRCULAR NUMBER: 15804 SUBJECT: Konus-Wind observation of GRB 140206B DATE: 14/02/07 08:29:36 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The long-duration intense GRB 140206B (Fermi-GBM detection: von Kienlin, GCN 15790; Fermi-LAT detection: Bissaldi et al., GCN 15791) triggered Konus-Wind at T0=23769.061 s UT (06:36:09.061). The light curve consists of two major multi-peaked emission episodes in the time interval from ~T0-3 s to ~T0+155 s. The emission is seen up to ~12 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB140206_T23769/ As observed by Konus-Wind, the burst had a fluence of (1.52 ± 0.09)x10-4 erg/cm2, and a 64-ms peak flux, measured from T0+7.488 s, of (1.73 ± 0.09)x10-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+154.368 s) is best fit in the 25 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -1.07 ± 0.08, the high energy photon index beta = -2.28 ± 0.09, the peak energy Ep = 227 ± 18 keV, chi2 = 93.8/96 dof. The spectrum near the maximum count rate (measured from T0+8.448 s to T0+16.384 s) is best fit in the 35 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.59 ± 0.08, the high energy photon index beta = -2.18 ± 0.04, the peak energy Ep = 278 ± 16 keV, chi2 = 84.3/93 dof. All the quoted results are preliminary.