[vsnet-grb-info 18170] Konus-Wind observation of GRB 160620A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19618
SUBJECT: Konus-Wind observation of GRB 160620A
DATE:    16/06/29 11:04:58 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

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 short GRB 160620A (IPN triangulation: Hurley et al., GCN 19594)
triggered Konus-Wind at T0=18380.236 s UT (05:06:20.236).

The light curve shows a single pulse which starts at ~T0-0.256 s,
peaks at ~T0+0.608, and have a total duration of ~1.5 s.
The emission is seen up to ~3 MeV.

As observed by Konus-Wind, the burst had a fluence
of 4.8(-0.6,+1.1)x10^-6 erg/cm2, and a 16-ms peak flux,
measured from T0+0.608 s, of 9.4(-0.6,+1.0)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+8.448 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 = -0.63 (-0.23,+0.35),
the high energy photon index beta = -3.41 (-6.59,+0.91),
the peak energy Ep = 158 (-27,+23) keV,
chi2 = 106/97 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160620_T18380/

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