An amplitude of 2-body process as shown in Fig.6 is produced by the
GRACE system. Following decays of;
,
,
and 
are treated as isotropic decays ignoring any spin information of
gauginos and a vector boson.
This approximation has two aspects;
and 
are very small, then this is good approximation.
However the width of W boson
is large compared with a Q-value of
a decay.
A virtuality of W-boson must affect distributions.