TITLE: GCN CIRCULAR NUMBER: 12064 SUBJECT: Konus-Wind observation of GRB 110604A DATE: 11/06/06 14:36:17 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 110604A (detected and localized by IPN and Swift-BAT: Barthelmy et al., GCN 12063) triggered Konus-Wind at T0=53385.666s UT (14:49:45.666) The burst light curve consists of several multi-peaked pulses, a total duration of the burst is ~45 s. The emission is seen up to ~8 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB110604_T53385/ As observed by Konus-Wind the burst had a fluence of (3.1 ± 0.3)x10-5 erg/cm2, and a 64-ms peak flux, measured from T0+2.880 s, of (4.6 ± 0.5)x10-6 erg/cm2/s (both in the 20 keV - 5 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+37.376 s) is best fitted in the 20 keV - 5 MeV range by the GRB (Band) model, for which: the low-energy photon index alpha = -1.10 (-0.08, +0.10), the high energy photon index beta = -3.2 (<-2.6), the peak energy Ep = 166(-16, +15) keV, chi2 = 71.7/76 dof. The spectrum at the maximum count rate (measured from T0 to T0+5.376 s) is best fitted in the 20 keV - 5 MeV range by the GRB (Band) model, for which: the low-energy photon index alpha = -0.8 (-0.1, +0.1), the high energy photon index beta = -3.0 (-2.5, +0.3), the peak energy Ep = 183(-14, +17) keV, chi2 = 64.7/70 dof. Also, both spectra show, in the 2-8 MeV range, a hint of a weak additional hard spectral component. All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.