Konus-Wind detection of a burst from SGR 1935+2154 on 2022 May 25

A short, soft, SGR-like burst triggered Konus-Wind on 2022 May 25 at T0=25816.58 s UT (07:10:16.580). The Konus-Wind ecliptic latitude response is consistent with the SGR 1935+2154 position. So, taking in account the ongoing bursting activity of this source, burst time history, and softness of its spectrum (as observed by Konus-Wind), we suggest that this burst is likely a SGR flare originated from SGR 1935+2154. The burst light curve shows a single pulse started at ~T0-72 ms with a total duration of ~194 ms. The emission is seen up to ~200 keV. The Konus-Wind light curve of this burst is available at http://www.ioffe.ru/LEA/SGRs/220525_T25816/ As observed by Konus-Wind, the burst had a fluence of 2.55(-0.10,+0.10)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0-0.014 s, of 2.08(-0.16,+0.16)x10^-5 erg/cm2/s (both in the 20 - 500 keV energy range). The spectrum of the burst (measured from T0 to T0+0.192 s) is best fit in the 20 - 200 keV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = 0.22(-0.54,+0.61) and Ep = 36(-3,+2) keV (chi2 = 20/18 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.