TITLE: GCN CIRCULAR NUMBER: 31433 SUBJECT: Konus-Wind detection of GRB 220101A DATE: 22/01/11 18:45:24 GMT FROM: Anastasia Tsvetkova at Ioffe Institute A. Tsvetkova, D. Frederiks, A. Lysenko, A. Ridnaia, D. Svinkin, M. Ulanov, and T. Cline on behalf of the Konus-Wind team, report: The long-duration, bright GRB 220101A (Swift-BAT trigger #1091101: Tohuvavohu  et al., GCN 31347; Markwardt et al., GCN 31369; Fermi-LAT detection: Arimoto et al., GCN 31350; AGILE detection: Ursi et al., GCN 31354; Fermi-GBM detection: Lesage & Meegan, GCN 31360) triggered Konus-Wind at T0=18695.828 s UT (05:11:35.828). The burst light curve shows a bright, multi-peaked pulse which starts at ~T0-147 s and has a total duration of~237 s. The emission is seen up to ~15 MeV. The total energy fluence of the burst is 9.05(-0.55,+0.60) erg/cm^2 and the 64-ms peak energy flux, measured from T0 + 18.624 s, is 4.0(-0.7, +0.7)x10^-6 erg/cm^2/s (both in the 10 keV - 10 MeV energy range). The time-averaged spectrum (measured from T0 to T0+90.112 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.58 (-0.13,+0.15), the high energy photon index beta = -2.62 (-0.53,+0.25), the peak energy Ep = 257 (-27,+28) keV, chi2 = 126/119 dof. The spectrum near the peak count rate (measured from T0+16.640 to T0+24.576 s) is best fit in the 20 keV - 15 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.51 (-0.16,+0.18), the high energy photon index beta = -2.55 (-0.64,+0.31), the peak energy Ep = 314 (-39,+43) keV, chi2 = 105/96 dof. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB220101_T18695/ Assuming the redshift z = 4.618 (Fynbo et al., GCN 31359) and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014), we estimate the following burst rest-frame parameters: the isotropic energy release Eiso = 3.64(-0.22,+0.25)x10^54 erg, which is in agreement with Atteia, GCN 31365; the isotropic luminosity Liso = 9.05(-1.58,+1.58)x10^53 erg/s; the rest-frame peak energy of the time-integrated spectrum Epi,z = 1416(-157,+152) keV; and the rest-frame peak energy of the 'peak' spectrum Epp,z = 1764(-219,+242) keV. With these values, GRB 220101A is within 68% prediction bands for for both 'Amati' and 'Yonetoku' relations for the sample of >300 long KW GRBs with known redshifts (Tsvetkova et al., 2021, ApJ, 908, 83), see http://www.ioffe.ru/LEA/GRBs/GRB220101_T18695/GRB220101A_rest_frame.pdf. All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.