[vsnet-grb-info 13708] Konus-Wind observation of GRB 130722A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15023
SUBJECT: Konus-Wind observation of GRB 130722A
DATE:    13/07/23 07:54:01 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

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

The long-duration GRB 130722A
(Swift-BAT trigger 563213: Troja, et al., GCN 15013)
triggered Konus-Wind at T0=30001.378 s UT (08:20:01.378).

The light curve  from ~T0-6 s to ~T0+55 s shows two main
emission pulses peaked at ~T0+1 s and ~T0+31 s, respectively.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB130722_T30001/

As observed by Konus-Wind, the burst
had a fluence of (2.35 ± 0.12)x10-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.256s,
of (1.84 ± 0.22)x10-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The 3-channel time-integrated spectrum
(measured from T0-6.663 to T0+55.191 s)
can be modeled, in the 20 keV - 1.35 MeV range,
by cutoff power law with the following model parameters:
the photon index alpha = -0.92 ± 0.03
and the peak energy Ep = 179 ± 5 keV,

The spectrum at the maximum count rate
(measured from T0 to T0+8.448 s)
is best fit, in the 20 keV - 5 MeV range,
by cutoff power law with the following model parameters:
the photon index alpha = -0.76 ± 0.12
and the peak energy Ep = 219 ± 15 keV,
chi2 = 90.3/76 d.o.f.

All the quoted results are preliminary.