Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 30418

Konus-Wind detection of a burst from SGR 1935+2154 on 2021 July 7
2021-07-08T15:20:32Z (3 years ago)
Anna Ridnaia at Ioffe Institute <>
A. Ridnaia, D. Frederiks, S. Golenetskii, A. Lysenko,
D. Svinkin, A. Tsvetkova,  M. Ulanov, and T. Cline
on behalf of the Konus-Wind team, report:

The short burst from SGR 1935+2154
(GECAM detection: Xiao et al., GCN 30400;
Fermi GBM Observations: Hamburg et al., GCN 30407)
triggered Konus-Wind on 2021 July 7 at
T0=2015.644 s UT (00:33:35.644).

The burst light curve shows a single pulse with a total
duration of ~120 ms. The emission is seen up to ~200 keV.

The Konus-Wind light curve of this GRB is available at

As observed by Konus-Wind, the burst
had a fluence of 1.48(-0.08,+0.08)x10^-6 erg/cm2,
and a 2-ms peak flux, measured from T0-0.014 s,
of 1.94(-0.39,+0.39)x10^-5 erg/cm2/s
(both in the 20 - 500 keV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+0.064 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 = 0.43(-0.80,+0.88)
and Ep = 38(-4,+3) keV (chi2 = 12/14 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
Looking for U.S. government information and services? Visit