GCN Circular 27867

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

The long-duration GRB 200524A
(Fermi-LAT detection: Fana Dirirsa et al., GCN Circ. 27797
Not found
 
 
;
Fermi-GBM detection: Pookalil et al., GCN Circ. 27809
Not found
 
 
;
AstroSat-CZTI detection: Gupta et al., GCN Circ. 27818
Not found
 
 
)
triggered Konus-Wind at T0=18243.246 s UT (05:04:03.246).

The burst light curve shows a multipeaked structure
which starts at ~T0-4.8 s, peaks at ~T0-3.3 s,
and to background level at ~T0+84 s.
The total burst duration is ~89 s.
The emission is seen up to ~10 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB200524_T18243/

As observed by Konus-Wind, the burst
had a fluence of 3.48(-0.62,+0.74)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+3.280 s,
of 6.33(-1.64,+1.75)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+40.704 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.75(-0.18,+0.25),
the high energy photon index beta = -2.13(-0.31,+0.20),
the peak energy Ep = 215(-46,+48) keV
(chi2 = 105/97 dof).

The spectrum near the maximum count rate
(measured from T0+0.256 to T0+7.936 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.55(-0.18,+0.26),
the high energy photon index beta = -2.14(-0.21,+0.16),
the peak energy Ep = 203(-36,+36) keV
(chi2 = 130/97 dof).

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