[vsnet-grb-info 22933] Konus-Wind observation of GRB 190704A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25032
SUBJECT: Konus-Wind observation of GRB 190704A
DATE:    19/07/08 13:14:30 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova at mail.ioffe.ru>

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

The short-duration, hard-spectrum
(IPN triangulation: Svinkin et al., GCN 25024)
triggered Konus-Wind at T0=22355.497 s UT (06:12:35.497).

The burst light curve shows a pulse with a duration of ~1.5 s
followed by a weaker pulse at ~T0+3.0.
The emission is seen up to ~16 MeV.

As observed by Konus-Wind, the burst
had a fluence of 3.56(-1.26,+3.48)x10^-6 erg/cm2,
and a 64-ms peak energy flux, measured from T0-0.310 s,
of 5.03(-2.48,+6.16)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 16 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.72(-0.41,+0.63),
and Ep = 861(-420,+2298) keV (chi2 = 21/20 dof).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB190704_T22355/

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.