TITLE: GCN CIRCULAR NUMBER: 17440 SUBJECT: Konus-Wind observation of GRB 150210A DATE: 15/02/11 15:04:47 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, and T. Cline on behalf of the Konus-Wind team, report: The long-duration, hard-spectrum GRB 150210A (Fermi-GBM detection: Burns, GCN 17432; Fermi-LAT detection: Zhu et al., GCN 17438; IPN triangulation: Golenetskii et al., GCN 17439) triggered Konus-Wind at T0=80787.209 s UT (22:26:27.209). The light curve shows a bright, multi-peaked pulse with a duration of ~3.5 s followed by a much weaker tail visible up to ~T0+30 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/GRB150210_T80787/ As observed by Konus-Wind, the burst had a fluence of 7.8(-0.8,+0.9)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+2.368 s, of 4.2(-0.3,+0.3)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+24.832 s) is best fit in the 20 keV - 15 MeV range by the cutoff power law with the following model parameters: the photon index alpha = -0.99(-0.07,+0.08), and the peak energy Ep = 2170(-340,+440) keV, chi2 = 107/98 dof. Fitting this spectrum with the Band model yields the same values of alpha and Ep with an upper limit on the high-energy photon index beta of -2.6 The spectrum near the peak count rate (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 15 MeV range by the cutoff power law with the following model parameters: the photon index alpha = -0.89(-0.06,+0.06), and the peak energy Ep = 2250(-240,+280) keV, chi2 = 126/98 dof. All the quoted errors are at the 90% sigma confidence level. All the quoted values are preliminary.