[vsnet-grb-info 26194] Konus-Wind detection of GRB 200826A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28294
SUBJECT: Konus-Wind detection of GRB 200826A
DATE:    20/08/27 13:29:13 GMT
FROM:    Anna Ridnaia at Ioffe Institute  <ridnaia at mail.ioffe.ru>

A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:

The short-duration GRB 200826A
(Fermi-GBM detection: The Fermi GBM Team, GCN Circ. 28284;
Mangan et al., GCN Circ. 28287;
BALROG localization: Kunzweiler et al., GCN Circ. 28286;
AstroSat-CZTI detection: Gupta et al.,  GCN Circ. 28288;
AGILE detection: Pittori et al.,  GCN Circ. 28289;
IPN triangulation: Hurley et al., GCN Circ. 28291)
triggered Konus-Wind at T0=16195.106 s UT (04:29:55.106).

The burst light curve shows a multipeaked pulse
which starts at ~T0-0.1 s with a total duration of ~1.6 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/GRB200826_T16195/

As observed by Konus-Wind, the burst
had a fluence of 3.30(-0.42,+0.47)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.560 s,
of 9.04(-2.49,+2.63)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 2 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = 1.27(-1.78,+4.03),
the high-energy photon index beta = -2.32(-0.25,+0.19),
the peak energy Ep = 67(-17,+31) keV
(chi2 = 50/59 dof).

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