TITLE: GCN CIRCULAR NUMBER: 22824 SUBJECT: Konus-Wind observation of GRB 180620A DATE: 18/06/22 15:25:50 GMT FROM: Dmitry Svinkin at Ioffe Institute D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 180620A (Swift-BAT detection: Evans et al., GCN Cric. 22798) triggered Konus-Wind at T0=30906.173 s UT (08:35:06.173). The burst light curve shows a multi-peaked structure which starts at ~T0-6.6 s and has a total duration of ~16 s. The emission is seen up to ~2 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB180620_T30906/ As observed by Konus-Wind, the burst had a fluence of 9.80(-1.02,+1.74)x10^-6 erg/cm2, and a 64-ms peak flux, measured from T0+7.504 s, of 2.69(-0.82,+0.94)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 4 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -1.19(-0.14,+0.16), the high energy photon index beta = -3.09(-6.91,+0.63), the peak energy Ep = 164(-24,+29) keV (chi2 = 70/75 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.