Muon decay asymmetries from kol yields pom+m-decays

摘要

We have examined the decay K(L) to pi(0) mu(+)mu(-) in which the branching ratio,the muon energy asymmetry and the muon decay asymmetry could be measured. In particular, we find that within the Standard Model the longitudinal polarization (PL) of the muon is proportional to the direct CP violating amplitude. On the other hand the energy asymmetry and the out-of-plane polarization (PN) depend on both indirect and direct CP violating amplitudes. Although the branching ratio is small and difficult to measure because of background, the asymmetries could be large O (1) in the Standard Model. A combined analysis of the energy asymmetry, PL and PN could be used to separate indirect CPV, direct CPV, and CP conserving contributions to the decay.