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 19613

Konus-Wind observation of a bright burst from SGR 1935+2154
2016-06-28T14:29:17Z (8 years ago)
Dmitry Frederiks at Ioffe Institute <>
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:

The bright burst from SGR 1935+2154 (Swift detection:
Barthelmy et al., GCN 19590; Cummings et al., GCN 19596;
Fermi/GBM detection: Younes et al., GCN 19598)
triggered Konus-Wind at T0=50073.909 s UT (13:54:33.909)
on 2016 June 26.

The light curve shows a single pulse with a sharp rise
and a total duration of ~0.8 s.
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 1.28(-0.02,+0.02)x10^-5 erg/cm2, and a 16-ms peak flux,
measured from T0, of 2.1(-0.1,+0.1)x10^-5 erg/cm2/s
(both in the 20 - 200 keV energy range).

The burst spectrum (measured from T0 to T0+0.256 s)
is well fit by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.17(-0.16,+0.16),
and Ep = 37.5(-1.1,+1.0) keV
(c-stat = 16.1/25 dof).
A double blackbody function fits this spectrum equally well
(c-stat = 17.3/26 dof), with
the cold BB temperature of 6.6 (-0.6,+0.6) keV and
the hot BB temperature of 13.9 (-0.6,+0.8) keV.

This event continues a series of about a dozen bright bursts
from SGR 1935+2154 detected by Konus-Wind in May-June, 2016.
Varying in their durations and energy fluences,
these bursts demonstrate spectral properties and peak
luminosities similar to those of the 1.7s-long "intermediate"
flare (IF) from this source (Kozlova et al. 2016, MNRAS 460, 2008).

All the quoted errors are at the 1 sigma confidence level.
All the quoted values are preliminary.
Looking for U.S. government information and services? Visit