GCN Circular 36886
Subject
Konus-Wind detection of GRB 240715A
Date
2024-07-16T12:54:31Z (3 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 240715A
(Fermi-GBM detection: The Fermi GBM team, GCN 36866;
de Barra & Meegan, GCN 36875;
IPN triangulation: Kozyrev at al., GCN 36872;
SVOM/GRM In-Flight Trigger: Huang et al., GCN 36881)
triggered Konus-Wind at T0=20645.475 s UT (05:44:05.475).
The burst light curve shows a single pulse,
which starts at ~T0 and has a total duration of ~0.2 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/GRB240715_T20645/
As observed by Konus-Wind, the burst
had a fluence of 7.00(-0.97,+1.02)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.090 s,
of 7.55(-1.72,+1.76)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+0.192 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 = -0.73(-0.13,+0.14)
and Ep = 1740(-328,+418) keV (chi2 = 24/48 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 = 24/47 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.