[AAVSO-HEN] Konus-Wind observation of GRB 080602

[grb at aavso.org]

The following is a GCN Circular circulated via the AAVSO network.
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TITLE:   GCN CIRCULAR
NUMBER:  7784
SUBJECT: Konus-Wind observation of GRB 080602
DATE:    08/06/02 16:44:25 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val at 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 second, most intense pulse of the GRB 080602 (Swift-BAT trigger 
#312958: Beardmore et al., GCN 7781) triggered Konus-Wind
at T0=5486.229 s UT (01:31:26.229).

As observed by Konus-Wind the burst
had a fluence of 7.92(-1.45, +1.47)x10^-6 erg/cm2,
and a 256-ms peak flux measured from T0+1.280 s
of (1.92 +/- 0.58)x10^-6 erg/cm2/s
(both in the 20 keV - 1 MeV energy range).

The spectrum of the most intense part
(from T0 to T0+8.448 s) is well fitted (in the 20 keV-1 MeV range)
by a simple power law with the photon index of 1.48(-0.17, +0.18) (chi2 
= 39.7/53 dof). We note that because of the derived photon index is <2,
the fluence is very sensitive to the upper boundary of the energy range.
Fitting by a power law with exponential cutoff model:
dN/dE ~ (E^-alpha)*exp(-E*(2-alpha)/Ep)
yields alpha = 0.96(-0.76, +0.52),
and only a lower limit on the peak energy: Ep > 226 keV
(chi2 = 36.6/52 dof).

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

The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB080602_T05486/