GCN Circular 35508
Subject
Konus-Wind detection of GRB 240101C
Date
2024-01-09T15:07:11Z (4 months ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
Via
Web form
A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The short-duration GRB 240101C
(Fermi-GBM detection: The Fermi GBM team, GCN 35451;
Bala et al., GCN 35488;
GRBAlpha detection: Dafcikova et al., GCN 35459;
AstroSat-CZTI detection: Navaneeth et al., GCN 35478;
Swift-BAT/GUANO detection: DeLaunay et al., GCN 35482;
IPN triangulation: Svinkin et al., GCN 35489)
triggered Konus-Wind at T0=46643.329 s UT (12:57:23.329).
The burst light curve shows a single pulse
which starts at ~T0-0.1 s and has a total duration of ~0.3 s.
The emission is seen up to ~4 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB240101_T46643/
As observed by Konus-Wind, the burst
had a fluence of 1.39(-0.19,+0.21)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.002 s,
of 1.57(-0.41,+0.43)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.19(-0.41,+0.52)
and Ep = 326(-56,+80) keV (chi2 = 15/22 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.4
(chi2 = 15/21 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.