GCN Circular 7589
Subject
Konus-Wind observation of GRB 080411
Event
Date
2008-04-12T08:39:42Z (18 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
and T. Cline on behalf of the Konus-Wind team report:
The long GRB 080411 (Swift-BAT trigger #309010: Marshall et al., GCN
7584) triggered Konus-Wind at T0=76532.496 s UT (21:15:32.496).
The burst light curve shows several pulses with a total duration of ~70s.
As observed by Konus-Wind the burst
had a fluence of 6.29(-0.29, +0.31)x10^-5 erg/cm2,
and a 64-ms peak flux measured from T0+17.936 s
of (1.28 +/- 0.16)x10^-5 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the burst
(from T0 to T0+74.24 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 = -1.51(-0.05, +0.04),
and Ep = 259(-27, +35) keV (chi2 = 64.5/59 dof).
All the quoted errors are at the 90% confidence level.
Assuming z = 1.03 (Thoene et al., GCN 7587) and a standard
cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, Omega_\Lambda =
0.73, the isotropic energy release is E_iso ~1.81x10^53 erg,
the maximum luminosity is (L_iso)_max ~7.48x10^52 erg/s, and
Ep_rest ~524 keV.
The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080411_T76532/