TITLE:   GCN CIRCULAR
NUMBER:  13382
SUBJECT: Konus-Wind observation of GRB 120624B
DATE:    12/06/25 17:39:20 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@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 intense hard GRB 120624B
(GBM trigger 362269436: Gruber et al., GCN 13377;
Fermi/LAT detection: Vianello & Kocevski, GCN 13379)
triggered Konus-Wind at T0=80406.904s UT (22:20:06.904)

The light curve shows multiple pulses grouped to three main episodes.
A total duration of the burst is ~300 s.

We note a quasi-periodic light curve structure (with T~3.6s)
which is observed during the second bursting episode
(from ~T0+120s to ~T0+150s).

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/GRB120624_T80406/

As observed by Konus-Wind the burst
had a fluence of 2.75(-0.1,+0.1)x10-4 erg/cm2,
and a 2.944-ms peak flux, measured from T0+235.28 s,
of 3.0(-0.6,+0.7)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst
(measured from T0 to T0+253.952 s)
is best fitted in the 20 keV - 10 MeV range
with the GRB (Band) model, for which:
the low-energy photon index alpha = -1.02 (-0.10, +0.12),
the high energy photon index beta = -2.6 (-2.0, +0.4),
the peak energy Ep = 530(-80, +90) keV,
chi2 = 82.7/86 dof.

The spectrum at the maximum count rate
(measured from T0+229.634 to T0+237.824 s)
is best fitted in the 20 keV - 10 MeV range
with the GRB (Band) model, for which:
the low-energy photon index alpha = -1.12 (-0.13, +0.21),
the high energy photon index beta = -2.3 (<-1.8),
the peak energy Ep = 1000(-450, +620) keV,
chi2 = 77.8/86 dof.

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