Decay rates and asymmetries in the case of a violating
interaction:
In the framework of the standard model and
because of the
rule:
Let us define:
We measure four rates:
1. :
at
and decay to
at time t:
2. :
at
and decay to
at time t:
3. :
at
and decay to
at time t:
4. :
at
and decay to
at time t:
In the case of the two decay rates forbidden by the
rule (
and
, we neglected
the terms proportional to
and
, which
are only important at short decay times
.
is a sign of direct
violation in the semileptonic
decay amplitude. It is difficult to distinguish this effect from
differences in the
and
decay rates due to different
and
tagging efficiencies and for the following we assume
.
with and