TITLE: GCN CIRCULAR NUMBER: 12153 SUBJECT: Konus-Wind observation of GRB 110708B DATE: 11/07/12 11:09:16 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The long bright GRB 110708B (localized by IPN: Golenetskii et al., GCN 12150) triggered Konus-Wind at T0=50386.394s UT (13:59:46.394) The burst light curve consists of three main pulse groups, with a total duration of ~60 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/GRB110708_T50386/ As observed by Konus-Wind the burst had a fluence of (9.4 ± 0.9)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+12.288 s, of (4.0 ± 0.5)x10-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (measured from T0 to T0+47.616 s) is best fitted in the 20 keV - 10 MeV range by the GRB (Band) model, for which: the low-energy photon index alpha = -0.78 (-0.08, +0.08), the high energy photon index beta = -2.4 (-0.2, +0.15), the peak energy Ep = 294(-28, +30) keV, chi2 = 67.8/84 dof. The spectrum at the maximum count rate (measured from T0+12.544 to T0+12.580 s) is best fitted in the 20 keV - 10 MeV range by the GRB (Band) model, for which: the low-energy photon index alpha = -0.55 (-0.12, +0.14), the high energy photon index beta = -3.3 (<-2.9), the peak energy Ep = 586(-81, +97) keV, chi2 = 33.3/47 dof. This spectrum is equally well fitted by a power law with exponential cutoff model, for which alpha = -0.59 (-0.07, +0.07), and Ep = 617(-69, +82) keV, chi2 = 34.2/48 dof. All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.