The most abundant and well known all-neutral and
decays are
-
and
-
(3
).
They are both 3
events and they can be used to check the
calibration of the Lead Glass Detector (LGD).
To examine 3
events, the invariant mass of every 2
pair
in 3-cluster events is formed. The plot of 2
invariant mass shows
two peaks one high and sharp corresponding to the
and
one less pronounced near the
mass.
This is used to select desired
or
events,
since
can come from
decay while
is
expected from
decay.