TITLE: GCN CIRCULAR NUMBER: 7884 SUBJECT: Konus-Wind observation of GRB 080613B DATE: 08/06/15 15:01:08 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team report: The long GRB 080613B (Swift-BAT trigger #313954: Markwardt et al., GCN 7873, Ukwatta et al., GCN 7876) triggered Konus-Wind at T0=40358.636 s UT (11:12:38.636). The burst light curve shows a multipeaked structure with a duration of ~30s. As observed by Konus-Wind the burst had a fluence of 2.21(-0.38, +0.44)x10^-5 erg/cm2, and a 256-ms peak flux measured from T0-0.144 s of 4.76(-1.24, +1.39)x10^-6 erg/cm2/s (both in the 20 keV - 3 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+33.024 s) is well fitted (in the 20 keV-3 MeV range) by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.05 +/- 0.18 and Ep = 733(-200, +285) keV (chi2 = 56.6/65 dof). Fitting by GRBM (Band) model yields the same alpha and Ep, and only an upper limit on the high energy photon index: beta < -2.05 (chi2 = 56.5/64 dof). All the quoted errors are at the 90% confidence level. The Konus-Wind light curve of this GRB is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080613_T40358/