[vsnet-grb-info 18403] Konus-Wind observation of GRB 160820A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19851
SUBJECT: Konus-Wind observation of GRB 160820A
DATE:    16/08/23 11:00:14 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin at mail.ioffe.ru>

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

The short-duration, hard-spectrum GRB 160820A
(IPN triangulation: Svinkin et al., GCN 19850)
triggered Konus-Wind at T0=42855.115 s UT (11:54:15.115).

The burst light curve shows a single pulse with a total duration
of ~0.2 s.

As observed by Konus-Wind, the burst
had a fluence of 7.54(-0.86,+0.94)x10^-7 erg/cm2
and a 16-ms peak flux, measured from T0-0.058 s,
of 5.63(-1.50,+1.52)x10^-6 erg/cm2/s
(both in the 20 - 1000 keV energy range).

Since a major fraction of the burst counts was accumulated
before the trigger, the spectral analysis was performed using
the KW 3-channel light curve data.
Modeling the 3-channel time-integrated spectrum
(measured from T0-0.158 s to T0+0.074 s)
by the cutoff power law yields the following model parameters:
the photon index alpha=0.87(-0.78,+2.13),
and the peak energy Ep=383(-67,+73) keV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160820_T42855/

All the quoted errors are at the 68% confidence level.
All the quoted values are preliminary.