TITLE:   GCN CIRCULAR
NUMBER:  17182
SUBJECT: Konus-Wind observation of GRB 141212B
DATE:    14/12/13 14:26:25 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration, weak GRB 141212B (Swift-BAT trigger #621234: 
Stamatikos et al., GCN 17159; Sakamoto et al., GCN 17176 ) triggered 
Konus-Wind at T0=48230.404 s UT (13:23:50.404).

The burst light curve shows a multipeak structure started at ~T0-6.8 s 
with a duration of ~8.0 s.
The emission is seen up to ~500 keV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB141212_T48230/

As observed by Konus-Wind, the burst
had a fluence of 1.65(-0.22,+0.38)x10^-6 erg/cm2,
and a 64-ms peak flux, measured from T0+0.014 s,
of 1.48(-0.24,+0.40)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+8.448 s)
is best fit in the 20 keV - 1 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with  alpha = -1.44(-0.28,+0.33)
and Ep = 150(-46,+136) keV (chi2 = 57/60 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -1.9
(chi2 = 56/59 dof)

All the quoted errors are at the 1 sigma confidence level.
All the quoted values are preliminary.