[vsnet-grb-info 15739] Konus-Wind observation of GRB 141104A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17027
SUBJECT: Konus-Wind observation of GRB 141104A
DATE:    14/11/05 14:18:31 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

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

The long-duration, very bright GRB 141104A
(IPN triangulation: Hurley et al., GCN 17026)
triggered Konus-Wind at T0=199.517 s UT (00:03:19.517).

The light curve shows a double-peaked structure with
a total duration of ~25 s.
The emission is seen up to ~10 MeV.

As observed by Konus-Wind, the burst had a fluence
of 5.9(-0.4,+0.4)x10^-5 erg/cm2, and a 64-ms peak flux,
measured from T0+8.064 s, of 1.6(-0.1,+0.1)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+27.136 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 = -1.09 (-0.11,+0.13),
the high energy photon index beta = -2.57 (-0.25,+0.15),
the peak energy Ep = 160 (-13,+16) keV,
chi2 = 96/96 dof.

The spectrum near the peak count rate (measured from T0+7.424 to T0+8.960 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 = -0.86 (-0.09,+0.11),
the high energy photon index beta = -3.32 (-0.81,+0.42),
the peak energy Ep = 232 (-18,+16) keV,
chi2 = 98/96 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB141104_T00199/

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