TITLE:   GCN CIRCULAR
NUMBER:  30467
SUBJECT: Konus-Wind detection of GRB 210714A
DATE:    21/07/18 14:11:31 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

D. Frederiks, S. Golenetskii, A.Lysenko, A. Ridnaia,
D. Svinkin, A. Tsvetkova,  M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:

GRB 210714A (Fermi-GBM trigger 647942198 / MASTER optical afterglow  detection: Lipunov et al., GCN 30466)
triggered Konus-Wind (KW) at T0=28598.602 s UT (07:56:38.602).

The burst light curve shows a bright, FRED-like pulse
which starts at ~T0-2.5 s, and has a total duration of ~80 s.
The emission is seen up to ~15 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB210714_T28598/

As observed by Konus-Wind, the burst had
a fluence of (9.6 ± 0.8)x10^-5 erg/cm^2 and
a 64-ms peak energy flux, measured from T0 + 1.664 s,
of (1.07 ± 0.10)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0 to T0+46.848 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 = -1.25 (-0.20,+0.49),
the high energy photon index beta = -1.83 (-0.06,+0.05),
the peak energy Ep = 145 (-60,+81) keV,
chi2 = 101/97 dof.

The spectrum near the peak count rate (measured from T0+0.256
to T0+5.888 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 = -1.01 (-0.30,+0.27),
the high energy photon index beta = -1.91 (-0.05,+0.04),
the peak energy Ep = 104 (-23,+39) keV,
chi2 = 111/97 dof.

All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.