TITLE: GCN CIRCULAR NUMBER: 13440 SUBJECT: Konus-Wind observation of GRB 120709A DATE: 12/07/11 11:55:36 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 GRB 120709A (GBM trigger 120709883: Guiriec et al., GCN 13429; Fermi/LAT detection: Kocevski et al., GCN 13423) triggered Konus-Wind at T0=76303.609s UT (21:11:43.609) The light curve shows multiple pulses grouped to three main episodes. A total duration of the burst is ~25 s. The emission is seen up to ~7 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB120709_T76303/ As observed by Konus-Wind the burst had a fluence of 1.8(-0.9,+1.0)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+11.968 s, of 6.4(-1.6,+2.5)x10-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (measured from T0 to T0+24.832 s) is well fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which: alpha = -0.86 (-0.25, +0.31), and Ep = 414(-117, +233) keV, chi2 = 75.8/84 dof. This spectrum is equally well fit by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.68 (-0.45, +0.56), the high energy photon index beta = -2.0 (<-1.7), the peak energy Ep = 296(-100, +356) keV, chi2 = 75.4/83 dof. The spectrum at the maximum count rate (measured from T0+8.848 to T0+16.640 s) is best fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which: alpha = -0.94 (-0.23, +0.28), and Ep = 643(-216, +470) keV, chi2 = 81.6/84 dof. All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.