[vsnet-grb-info 8849] Konus-Wind observation of GRB 100116A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10347
SUBJECT: Konus-Wind observation of GRB 100116A
DATE:    10/01/19 13:23:06 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin,
P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf
of the Konus-Wind team, report:

The long hard GRB 100116A (Fermi-GBM trigger 285370262:
Briggs and Connaughton, GCN 10330;
Fermi-LAT localization: McEnery et al., GCN 10333)
triggered Konus-Wind at T0=77543.747s UT (21:32:23.747)

The burst light curve shows a single-pulse structure
with a total duration of ~30 s. A weaker precursor, reported by
Fermi-GBM (GCN 10330) is clearly seen in the low-resolution
background mode data at T0-88s.
The emission is seen up to 10 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100116_T77543/

As observed by Konus-Wind the burst
had a fluence of 5.7(+/-0.6)x10-5 erg/cm2,
and a 256-ms peak flux measured from T0+6.144s
of 4.2(+/-0.4)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+23.296 s) is well be fitted
in the 20 keV - 10 MeV range by a power law
with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep), with
alpha = -0.96(-0.06, +0.07),
and Ep = 968(-130, +163) keV (chi2 = 105/98 dof).

The spectrum of the most intense part of the burst
(measured from T0+0.256 to T0+8.192 s) is well fitted
in the 20 keV - 10 MeV range by a power law
with exponential cutoff model, for which
alpha = -0.96(+/-0.6),
and Ep = 1015(-121, +146) keV (chi2 = 107/101 dof).

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