TITLE:   GCN CIRCULAR
NUMBER:  11723
SUBJECT: Konus-Wind observation of GRB 110213A
DATE:    11/02/14 11:36:03 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

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

The long GRB 110213A, (Swift/BAT trigger=445414:
D'Elia, et al., GCN 11705; Barthelmy et.al, GCN 11714)
triggered Konus-Wind at T0=19048.893s UT (05:17:28.893)

The burst light curve consists of a single pulse
with a total duration of ~50 s.
The emission is seen up to ~2 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB110213_T19048/

As observed by Konus-Wind the burst
had a fluence of (1.0 ± 0.15)x10-5 erg/cm2,
and a 256-ms peak flux, measured from T0+1.024s,
of (1.4 ± 0.2)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+24.832 s) is best fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -1.65 (-0.2, +0.3),
and Ep = 91(-26, +31) keV,
chi2 = 62.5/61 dof.

The spectrum at the maximum count rate
(measured from T0 to T0+8.448 s) is well fitted
in the 20 keV - 2 MeV range by a power law
with exponential cutoff model, for which
alpha = -1.53 (-0.21, +0.24),
and Ep = 110(-20, +32) keV,
chi2 = 52.8/61 dof.
This spectrum is nearly well fitted
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -1.28 (-0.32, +0.44),
the high energy photon index beta = -2.4 (-0.7, +0.2),
the peak energy Ep = 89(-19, +28) keV,
chi2 = 49.1/60 dof.

Assuming the Bok telescope redshift z = 1.46 (Milne & Cenko, GCN 11708)
and a standard cosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27,
Omega_Lambda = 0.73, the isotropic energy release
E_iso is (5.5 ± 0.08)x10^52 erg, the peak luminosity
L_iso_max is (1.9 ± 0.3)x10^52 erg/s,
and Ep_rest is 224 ± 74 keV.


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