TITLE: GCN GRB OBSERVATION REPORT NUMBER: 4564 SUBJECT: Konus-Wind observation of GRB 060121 DATE: 06/01/22 18:37:03 GMT FROM: Valentin Pal'shin at Ioffe Inst S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and T. Cline on behalf of the Konus-Wind team report: The GRB 060121 (=H4010; Arimoto et al., GCN 4550; Prigozhin et al., GCN 4551) triggered Konus-Wind at T0=80700.890 s UT (22:25:00.890). The Konus-Wind light curve shows a single pulse with a duration of ~2 sec. As observed by Konus-Wind the burst had a fluence of 4.71(-3.71,+0.44)x10^-6 erg/cm2 and peak flux measured from T0+0.448 sec on 64 msec time scale 1.64(-1.32,+0.18)x10^-5 erg/cm2/sec (both in the 20 keV - 1 MeV energy range). The time-integrated spectrum of the GRB is well fitted (in the 20 keV - 1 MeV range) by GRBM (Band) model for which: the low-energy photon index is alpha = -0.51(-0.60,+0.55), the high energy photon index beta = -2.39(-1.41,+0.27), the break energy E0 = 70(-52, +90) keV (chi2 = 59/59 dof). The fitting by a power law with exponential cutoff model: dN/dE ~ E^(-alpha) * exp(-E*(2-alpha)/Ep) in the same energy range gives alpha = 0.82(-0.21,+0.38) and Ep = 134(-17, +32) keV (chi2 = 63/60 dof). All the quoted errors are at the 90% confidence level.