GCN Circular 44286
Subject
Konus-Wind detection of GRB 260410A (short/hard)
Event
Date
2026-04-13T11:52:18Z (2 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 260410A
(Fermi-GBM detection: Fermi GBM team, GCN Circ. 44252,
Hamburg et al., GCN Circ. 44258;
Fermi-LAT detection: Holzmann Airasca et al., GCN Circ. 44253;
CALET-GBM detection: Ricciarini et al., GCN Circ. 44283)
triggered Konus-Wind at T0=25436.09 s UT (07:03:56.090).
The burst light curve shows a multipeaked structure,
which starts at ~T0-0.1 s and has a total duration of ~0.3 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/GRB260410_T25436/
As observed by Konus-Wind, the burst
had a fluence of 3.36(-0.54,+0.53)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.054 s,
of 2.53(-0.69,+0.68)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 the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.06(-0.34,+0.62),
the high energy photon index beta = -2.06(-0.51,+0.28),
the peak energy Ep = 784(-283,+341) keV
(chi2 = 21/27 dof).
All the quoted errors are at the 68% confidence level.
All the quoted values are preliminary.