GCN Circular 38304
Subject
Konus-Wind detection of GRB 241117A
Date
2024-11-24T15:43:17Z (10 days ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
Via
Web form
V. Panteleeva, D. Frederiks, A. Lysenko, A. Ridnaia,
D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The long-duration (or possible short GRB with extended emission;
Fermi-GBM detection: The Fermi GBM Team, GCN 38258;
Scotton and Meegan, GCN 38265;
SVOM-GRM observation: Wang et al., GCN 38266;
Swift-BAT/GUANO detection: Ronchini et al., GCN 38273;
IPN triangulation: Kozyrev et al., GCN 38300)
triggered Konus-Wind at T0=10845.029 s UT (03:00:45.029).
The burst light curve shows the initial short-duration,
bright multipeaked emission episode which starts at ~T0-0.2 s
and has a total duration of ~1.8 s, followed by a weaker
emission traced up to ~77 s.
The emission is seen up to ~5 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB241117_T10845/
As observed by Konus-Wind, the burst initial pulse
had a fluence of 1.24(-0.16,+0.34)x10^-5 erg/cm2,
and a 16-ms peak flux, measured from T0+0.132 s,
of 1.72(-0.53,+0.67)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the initial episode
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 16 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.39(-0.27,+0.40),
the high energy photon index beta = -3.54(-6.46,+1.20),
the peak energy Ep = 733(-178,+204) keV
(chi2 = 50/79 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.