GCN Circular 21247
Subject
Konus-Wind observation of GRB 170604A
Date
2017-06-11T15:27:18Z (7 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:
The long GRB 170604A (Swift-BAT trigger #736407: Page et al.,
GCN 21191; Stamatikos et al., GCN 21195; T0(BAT)=17:08:50.402 UT)
was detected by Konus-Wind (KW) in the waiting mode.
The light curve shows a single peak with a duration of ~30 s.
Modeling the KW 3-channel time-integrated spectrum
(from T0(BAT)-16.155 s to T0(BAT)+10.341 s) by
a power law with exponential cutoff (CPL) model
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -1.31(-0.20,+0.26) and Ep = 220(-48,+72) keV.
The energy fluence for this time interval is (1.03 �� 0.13)x10^-5
erg/cm2, and the peak energy flux, measured on a 2.944 s scale from
T0(BAT)+1.509 s is (6.9 �� 0.13)x10^-7 erg/cm2/s, both in the
20 keV-10 MeV range.
Assuming the redshift z=1.329 (Izzo et al., GCN 21197)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.30, and Omega_Lambda = 0.70, we estimate the burst
isotropic energy release E_iso to (4.7 �� 0.6)x10^52 erg,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,z, to 512(-112,+168) keV.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB170604A/
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.