TITLE: GCN CIRCULAR NUMBER: 13412 SUBJECT: Konus-Wind observation of GRB 120703A DATE: 12/07/04 07:58:07 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 120703A (Swift-BAT trigger #525671: B.-B. Zhang et al., GCN 13408) triggered Konus-Wind at T0=62723.578s UT (17:25:23.578) The burst light curve shows a single peak with a total duration of ~12.5 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/GRB120703_T62723/ As observed by Konus-Wind the burst had a fluence of (7.7 ± 1.0)x10-6 erg/cm2, and a 64-ms peak flux, measured from T0+0.960 s, of (5.4 ± 1.3)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+8.448 s) is well fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which: alpha = -0.81 (-0.25, +0.30), and Ep = 295(-56, +88) keV, chi2 = 96.8/84 dof. Fitting this spectrum with the GRB (Band) function yields the following model parameters: the low-energy photon index alpha = -0.67 (-0.37, +0.54), the high energy photon index beta = -2.7 (<-2.3), the peak energy Ep = 256(-75, +100) keV, chi2 = 96.4/83 dof. The spectrum at the maximum count rate (measured from T0 to T0+0.256 s) is best fitted is best fit in the 20 keV - 10 MeV range by a power law with exponential cutoff model, for which: alpha = -0.50 (-0.37, +0.46), and Ep = 410(-90, +150) keV, chi2 = 21.5/22 dof. All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.