RICH Chrenkov counter is used for identification
of chraged pions in higher 
than 5.5 GeV/c.
The threshold behavior of the real
data shown in Fig. 9 are
well described by the estimation numbers shown
in the solid line..
Note that the contamination of electron is about one
tenth of 1 % in this momentum region. And the ring image
are shown in the inset of Fig. 9 (note that
multiple tracks are accumulated).
The identification of pion by RICH has provided inclusive pion
spectra from 5.5 GeV/c up to 10 GeV/c in .