[vsnet-grb-info 18091] Konus-Wind observation of GRB 160612A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  19539
SUBJECT: Konus-Wind observation of GRB 160612A
DATE:    16/06/15 13:59:33 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova at mail.ioffe.ru>

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

The short-duration, hard-spectrum GRB 160612A
(Fermi GBM detection: Burns, Meegan & Jenke, GCN 19531;
IPN triangulation: Kozlova et al., GCN 19535;
BAT detection and localization:  Lien & Palmer, GCN 19537)
triggered Konus-Wind at T0=72767.893 s UT (20:12:47.893).

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 1.02(-0.13,+0.12)x10^-6 erg/cm2
and a 16-ms peak flux, measured from T0-0.074 s,
of 1.16(-0.26,+0.26)x10^-5 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 T0-0.128 s to T0+0.064 s)
by the cutoff power law yields the following model parameters:
the photon index alpha=-0.54(-0.38,+0.53),
and the peak energy Ep=1.46(-0.62,+8.00) MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160612_T72767/

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