[vsnet-grb-info 17450] Konus-Wind observation of GRB 160113A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18876
SUBJECT: Konus-Wind observation of GRB 160113A
DATE:    16/01/17 14:23:27 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

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

The long-duration GRB 160113A
(Fermi-GBM detection: Roberts & Burns, GCN 18861;
IPN triangulation: Hurley et al., GCN 18871)
triggered Konus-Wind at T0=34379.515 s UT (09:32:59.515).

The light curve shows a smooth pulse in the interval
from ~T0-5 s to ~T0+20 s, preceded by a much weaker pulse
around ~T0-28 s.
The emission is seen up to ~7 MeV.

As observed by Konus-Wind, the burst had a fluence
of 2.4(-0.1,+0.1)x10^-5 erg/cm2, and a 64-ms peak flux,
measured from T0+5.184 s, of 4.0(-0.3,+0.4)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+21.248 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 = -0.51 (-0.15,+0.17),
the high energy photon index beta = -3.55 (-0.83,+0.37),
the peak energy Ep = 97 (-4,+4) keV,
chi2 = 71.7/97 dof.

The spectrum near the peak count rate (measured from T0+0.256
to T0+8.192 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 = -0.24 (-0.19,+0.24),
the high energy photon index beta = -3.36 (-0.71,+0.39),
the peak energy Ep = 130 (-9,+8) keV,
chi2 = 71.5/97 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160113_T34379/

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