TITLE: GCN CIRCULAR NUMBER: 10890 SUBJECT: Konus-Wind observation of GRB 100625A DATE: 10/06/26 10:28:51 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 short hard GRB 100625A (Swift-BAT trigger #425647: Holland et al., GCN 10884) triggered Konus-Wind at T0=66747.799 s UT (18:32:27.799). The burst light curve consists of two main peaks separated by ~100 ms, with a total duration of the burst of ~350 ms. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB100625_T66747/ As observed by Konus-Wind the burst had a fluence of 0.83(+/-0.15)x10-6 erg/cm2, and a 16-ms peak flux measured from T0 + 0.128s of 8.1(+/-1.5)x10-6 erg/cm2/s (both in the 20 keV - 2 MeV energy range). The time-integrated spectrum of the burst (from T0 to T0+0.192 s) is well fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with alpha = -0.1(-0.5, +0.6), and Ep = 414(-78,+128) keV, chi2 = 18/18 dof. This spectrum is equally well fit in the same range by the GRB (Band) model, for which: the low-energy photon index alpha = +0.1 (+/-0.6), the high energy photon index beta = -2.6 ( <-1.9 ), the peak energy Ep = 371(-100,+135) keV, chi2 = 17/17 dof. All the quoted results are preliminary. All the quoted errors are at the 90% confidence level.