TITLE: GCN CIRCULAR NUMBER: 14005 SUBJECT: Konus-Wind observation of GRB 121122A DATE: 12/11/27 12:04:59 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-duration intense GRB 121122A (IPN detection and localization: Hurley et al., GCN 14001) triggered Konus-Wind at T0=76497.048s UT (21:14:57.048) The burst light curve is formed by three overlapped FRED-like pulses; a total duration of the burst is ~12 s. A behavior of hardness ratios between the instrument's light curves in different energy bands suggests a strong hard-to-soft spectral evolution. The emission is seen up to 7 MeV. As observed by Konus-Wind, the burst had a fluence of (4.1 ± 0.1)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+1.728 s, of (1.0 ± 0.1)x10-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum of the burst (measured T0 to T0+15.616 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.53 ± 0.05, the high energy photon index beta = -3.3 ± 0.2, the peak energy Ep = 183 ± 4 keV, chi2 = 106/91 dof. The spectrum at the maximum count rate (measured T0 to T0+1.792 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = +0.58 ± 0.12, the high energy photon index beta = -3.0 ± 0.2, the peak energy Ep = 308 ± 13 keV, chi2 = 69.4/60 dof. The time-resolved spectral analysis reveals a steady decrease of Ep from ~700 keV to ~100 keV during the first 8 seconds of the burst, which can be described by a power law with the temporal decay index of ~0.6 . The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB121122_T76497/ All the quoted results are preliminary.