GCN Circular 38881
Subject
Konus-Wind detection of GRB 250107D (short/hard)
Date
2025-01-09T22:08:34Z (a month ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
Via
email
D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The short GRB 250107D (IPN triangulation: Kozyrev et al., GCN 38880)
triggered Konus-Wind (KW) at T0=19411.897 s UT (05:23:31.897).
The burst light curve shows a single, multi-peaked emission pulse
which starts at ~T0-0.112 s and has a duration of ~0.208 s.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB250107_T19411/
As observed by Konus-Wind, the burst had
the total fluence of 2.06(-0.34,+0.62)x10^-6 erg/cm^2
and a 16-ms peak energy flux, measured from T0-0.064 s,
of 1.99(-0.32,+0.59)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).
Since a major part of the burst emission was detected before the trigger time,
the time-averaged spectral analysis was performed using the KW 3-channel light curve data.
Modeling the 3-channel time-integrated spectrum (measured from T0-0.112 s to T0+0.096 s)
by a power law with exponential cutoff (CPL) model dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -0.40 (-0.32, + 0.41) and Ep = 897(-203,+453) keV.
All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.