[vsnet-grb-info 20319] Konus-Wind observation of GRB 180210A

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22415
SUBJECT: Konus-Wind observation of GRB 180210A
DATE:    18/02/14 13:27:42 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin at mail.ioffe.ru>

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

The long-duration GRB 180210A
(Fermi-GBM detection: Bissaldi, GCN Circ. 22407;
Fermi-LAT detection: Dirirsa and Bissaldi, GCN Circ. 22407)
triggered Konus-Wind at T0=44678.454 s UT (12:24:38.454).

The burst light curve shows a multipeaked structure
which starts at ~T0-6 s and has a total duration of ~65 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/GRB180210_T44678/

As observed by Konus-Wind, the burst
had a fluence of 4.81(-0.30,+0.36)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+20.224 s,
of 5.35(-1.07,+1.10)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum of the burst
(measured from T0 to T0+47.360 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 = -0.49(-0.13,+0.15),
the high energy photon index beta = -3.12(-0.54,+0.30),
the peak energy Ep = 153(-8,+8) keV
(chi2 = 84/97 dof).

The spectrum near the maximum count rate
(measured from T0+16.128 to T0+22.784 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 = -0.08(-0.24,+0.27),
the high energy photon index beta = -3.25(-1.02,+0.37),
the peak energy Ep = 152(-11,+12) keV
(chi2 = 106/91 dof).

All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.