[vsnet-grb-info 15082] Konus-Wind observation of GRB 140606B

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16374
SUBJECT: Konus-Wind observation of GRB 140606B
DATE:    14/06/10 12:20:20 GMT
FROM:    Anastasia Tsvetkova at Ioffe Institute  <tsvetkova at mail.ioffe.ru>

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

The long-duration GRB 140606B (Fermi-GBM detection: Burns, GCN 16319;
IPN triangulation: Golenetskii et al., GCN 16369) triggered Konus-Wind
at T0=11510.769 s UT (03:11:50.769).

The burst light curve shows a single pulse with a duration of ~8 s.
The emission is seen up to ~5 MeV.

As observed by Konus-Wind, the burst had a fluence of
6.6(-0.5,+0.5)x10^-6 erg/cm2, and a 64-ms peak flux, measured from
T0+0.752 s, of 2.9(-0.7,+0.7)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 5 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.60(-0.18,+0.20),
and Ep = 254(-27,+33) keV (chi2 = 78/73 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.9
(chi2 = 78/72 dof).

Assuming the redshift z=0.384 (Perley et al., GCN 16365)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, and Omega_Lambda = 0.73,
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is 2.5(-0.2,+0.2)x10^51 erg,
the peak luminosity L_iso is 1.5(-0.4,+0.4)x10^51 erg/s,
and the rest-frame peak energy, Ep,i, is 352(-37,+46) keV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB140606_T11510/

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