INFN - Laboratori Nazionali di Frascati, May 1995
From: The Second DAFNE Physics Handbook
Chapter 8: $eta$ Decays
Eds. L. Maiani, G. Pancheri, N. Paver
Supported by the INFN, by the EC under the HCM contract number CHRX-CT920026 and by the authors home institutions.
Mesons
ITEP, Moscow
NE facilities, an observation of the weak decays of 
mesons would be an evidence of new physics beyond the Standard Model.
As it was pointed in ref. [1] a study of the 
and
electromagnetic decays of 
mesons at the DA
NE 
-factory
will improve a precision in determination of C-violating part of the
amplitudes by one-two orders. A comparatively big number of 
mesons
/year expected at the DA
NE machine makes
also pertinent the question on possibility to observe the weak decays of
mesons.
These decays possess some specific properties which would be not harm to verify. Namely, because of G-parity conservation [2] the decays
are suppressed in comparison with the analogous decays of 
mesons
possessing the same CP-properties as 
.
The decays
are allowed, but they are suppressed compare to
decay by the momentum-space factor 
.
Of the nonleptonic weak decays the decay
is the most interesting as it needs CP violation and it can not be masked by
strong interaction contribution as in the case of 
decay.
Let's consider the above mentioned processes in details.