GCN Circular 8610
Subject
Konus-Wind observation of GRB 081203B
Date
2008-12-04T12:34:28Z (15 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@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 Swift-BATSS GRB 081203B (Copete et al., GCN 8600, 8602)
triggered Konus-Wind at T0=49890.368 s UT (13:51:30.368).
The burst light curve shows a multipeaked structure with a total
duration of ~80 s.
As observed by Konus-Wind the burst
had a fluence of 5.56(-0.23, +0.24)x10^-5 erg/cm2,
and a 256-ms peak flux measured from T0+10.032 s
of 2.43(-0.40, +0.41)x10^-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the burst
(from T0 to T0+64.000 s) can be fitted (in the 20 keV-2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -1.165(-0.054, +0.057),
and Ep = 255(-19, +22) keV (chi2 = 77.8/61 dof).
Fitting by GRB (Band) model yields the same alpha and Ep,
and only an upper limit on the high energy
photon index: beta < -2.59 (chi2 = 77.7/60 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/GRB081203_T49890/
[GCN OPS NOTE(04dec08): Per author's request, the authors
were added.]