TITLE: GCN CIRCULAR NUMBER: 17351 SUBJECT: Konus-Wind observation of GRB 150123A DATE: 15/01/26 18:06:25 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, 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 150123A localized by MAXI/GSC (Fukushima et al., GCN 17345) was detected by Konus-Wind in the waiting mode. The burst light curve shows a single pulse started at ~T0(MAXI)-39 s with a duration of ~70 s. As observed by Konus-Wind, the burst had a fluence of 7.42(-0.80,+0.88)x10^-6 erg/cm2 and a 2.944-s peak flux, measured from ~T0(MAXI)-1 s, of (1.6 +/- 0.7)x10^-7 erg/cm2 (both in the 20 - 1200 keV energy range). Fitting the K-W 3-channel time-integrated spectrum (from T0(MAXI)-39 s to T0(MAXI)+31 s) by a simple power-law model yields a power law index of 1.82 +/- 0.1 (chi2=1.0/1 dof). All the quoted errors are estimated at the 1 sigma confidence level. All the presented results are preliminary. The K-W light curve of this burst is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB150123A/