[vsnet-grb-info 24049] Konus-Wind observation of GRB 191031D: correction to GCN 26126

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26149
SUBJECT: Konus-Wind observation of GRB 191031D: correction to GCN 26126
DATE:    19/11/03 11:15:05 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred at mail.ioffe.ru>

D. Frederiks, on behalf of the Konus-Wind team:

Reported in Frederiks et al. 2019 (GCN Circ. 26126),
the KW spectral parameters and fluxes of short/hard GRB 191031D
are incorrect due to wrong instrument calibrations used.
The correct values are given below.

As observed by Konus-Wind, the burst had a fluence
of 5.72(-0.63,+0.69)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.016 s,
of 4.12(-0.72,+0.80)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-integrated spectrum of the burst (measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -0.12(-0.18,+0.20)
and Ep = 735(-92,+112) keV (chi2 = 32/39 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 =32/38 dof).

I apologize for possible inconvenience this may have caused.