[vsnet-grb-info 12662] Konus-Wind observation of GRB 121127A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14022
SUBJECT: Konus-Wind observation of GRB 121127A
DATE:    12/11/30 07:37:36 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 121127A
(IPN localization: Golenetskii at al., GCN 14021)
triggered Konus-Wind at T0=78957.290s UT (21:55:57.290)

The light curve shows a single pulse with a duration of ~0.25 s.
The emission is seen up to ~6 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB121127_T78957/

As observed by Konus-Wind the burst
had a fluence of (3.8 ± 0.8)x10-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.016 s,
of (2.6 ± 0.6)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 = 0.0 ± 0.3,
the high energy photon index beta = -2.0 ± 0.3,
the peak energy Ep = 600 ± 170 keV,
chi2 = 11/19 dof.

All the quoted results are preliminary.