[vsnet-grb-info 8459] Konus-Wind observation of GRB 090929B

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9975
SUBJECT: Konus-Wind observation of GRB 090929B
DATE:    09/09/30 13:30:14 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val at mail.ioffe.ru>

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

The long GRB 090929B (Swift-BAT trigger #371050: Pagani et al., GCN 
9963) triggered Konus-Wind at T0=36565.377 s UT (10:09:25.377).

The burst light curve shows a multipeaked structure with a total
duration of ~20 s.

As observed by Konus-Wind the burst
had a fluence of (1.16 +/- 0.12)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+16.208 s
of (3.80 +/- 0.90)x10^-6 erg/cm2/s
(both in the 20 keV - 1 MeV energy range).

The time-integrated spectrum of the burst
(from T0 to T0+16.640 s) is well fitted (in the 20 keV - 1 MeV
range) by GRB (Band) model for which:
the low-energy photon index alpha = -0.41 (-0.77, +1.16),
the high energy photon index beta = -1.82(-0.59, +0.24),
the peak energy Ep = 282(-78, +169) keV (chi2 = 52.4/59 dof).

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

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.ru/LEA/GRBs/GRB090929_T36565/