[vsnet-grb-info 13011] Konus-Wind observation of GRB 130327B

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14348
SUBJECT: Konus-Wind observation of GRB 130327B
DATE:    13/03/28 09:37:10 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-duration GRB 130327B
(AGILE detection: Longo et al., GCN 14344;
Fermi-GBM detection: Chaplin and Fitzpatrick, GCN 14346;
Fermi-LAT detection: Ohno et al., GCN 14347)
triggered Konus-Wind at T0=30247.662s UT (08:24:07.662)

The light curve shows a multi-peaked structure
with a total duration of ~35 s.
The emission is seen up to 12 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB130327_T30247/

As observed by Konus-Wind, the burst
had a fluence of (5.6 ± 0.5)x10-5 erg/cm2,
and a 64-ms peak flux, measured from T0+4.352s,
of (4.9 ± 0.5)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum (measured from T0 to T0+40.704 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 = -0.59 ± 0.08,
the high energy photon index beta = -2.65 ± 0.25,
the peak energy Ep = 278 ± 18 keV,
chi2 = 122/97 dof.

The spectrum at the maximum count rate (measured from T0 to T0+7.936 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 = -0.62 ± 0.13,
the high energy photon index beta = -2.6 ± 0.4,
the peak energy Ep = 314 ± 39 keV,
chi2 = 97.6/92 dof.

All the quoted results are preliminary.