GCN Circular 28744
Subject
Konus-Wind detection of GRB 201020A
Event
Date
2020-10-22T12:51:04Z (5 years ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@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 long-duration GRB 201020A
(Swift-BAT trigger #1000926: Ambrosi et al., GCN 28696;
Sakamoto et al., GCN 28705; T0(BAT)=05:47:26.16 UT;
Fermi-GBM observation: Bissaldi et al., GCN 28706)
was detected by Konus-Wind (KW) in the waiting mode.
The burst light curve shows a single emission episode
with a duration of ~ 15 s.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB201020A/
As observed by Konus-Wind, the burst had a fluence of
1.38(-0.23,0.45)x10^-6 erg/cm2 and a 2.944-s peak flux,
measured from ~T0(BAT)+16.5 s, of 1.34(-0.28,+0.47)x10^-7 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The K-W 3-channel time-integrated spectrum
(from ~T0(BAT)+10.6 s to ~T0(BAT)+25.3 s)
is best described by simple power-law model
with photon index of -2.41(-0.12,+0.17), chi2=0.06/1 dof.
Assuming the redshift z=2.903 (Kann et al., GCN 28717)
and a standard cosmology model with H_0 = 67.3 km/s/Mpc,
Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~2.6x10^52 erg,
and the peak luminosity L_iso is ~1.0x10^52 erg/s.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.