[vsnet-grb-info 12503] Konus-Wind observation of GRB 121011B

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13870
SUBJECT: Konus-Wind observation of GRB 121011B
DATE:    12/10/15 11:10:07 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 short-duration hard-spectrum GRB 121011B
(IPN localization: Golenetskii at al., GCN 13863)
triggered Konus-Wind at T0=81140.083s UT (22:32:20.083)

The light curve shows a single pulse with a duration of ~0.35 s.
The emission is seen up to ~7 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB121011_T81140/

As observed by Konus-Wind the burst
had a fluence of (2.8 ± 0.3)x10-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.112 s,
of (2.3 ± 0.4)x10-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The spectrum of the burst (measured T0 to T0+0.192 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.45 ± 0.37,
the high energy photon index beta = -1.9 ± 0.4,
the peak energy Ep = 670 ± 340 keV,
chi2 = 16.3/17 dof.

All the quoted results are preliminary.