[vsnet-grb-info 23214] Konus-Wind observation of GRB 190810А

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25313
SUBJECT: Konus-Wind observation of GRB 190810А
DATE:    19/08/12 11:39:06 GMT
FROM:    Anna Kozlova at Ioffe Institute  <ann_kozlova at mail.ioffe.ru>

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:

The short-duration GRB 190810A
(IPN triangulation: Hurley et al., GCN 25312)
triggered Konus-Wind at T0=58318.421 s UT (16:11:58.421).

The burst light curve shows a single pulse
which starts at T0-0.1 s and has a total duration of ~0.2 s.

As observed by Konus-Wind, the burst
had a fluence of 2.29(-0.40,+0.85)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.042 s,
of 2.23(-0.55,+0.92)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

Since the most intense part of the burst was detected before
the trigger, the spectral analysis was performed using
the KW 3-channel light curve data.

Modeling the KW 3-channel time-integrated spectrum
(from T0-0.098 s to T0+0.088 s)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -0.61 (-0.22,+0.27), and Ep = 1120 (-266,+656) keV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB190810_T58321/

All the quoted errors are at the 68% confidence level.
All the quoted values are preliminary.