GCN Circular 20952
Subject
Konus-Wind observation of GRB 170329A
Date
2017-03-31T10:56:46Z (8 years ago)
From
Anna Kozlova at Ioffe Institute <ann_kozlova@mail.ioffe.ru>
A.Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:
The long-duration GRB 170329A (Fermi-LAT detection: Yassine et al., GCN
20942; Fermi-GBM detection: Bissaldi et al., GCN 20943)
triggered Konus-Wind at T0=33423.095 s UT (09:17:03.095).
The burst light curve shows a single multi-peaked pulse
with a total duration of ~7 s. The emission is seen up to ~6 MeV.
As observed by Konus-Wind, the burst
had a fluence of 1.47(-0.18,+0.22)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.346 s,
of 4.74(-1.61,+1.66)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 6 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.30(-0.25,+0.30)
and Ep = 688(-109,+153) keV (chi2 = 63/81 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.3
(chi2 = 63/80 dof)
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB170329_T33423/
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.