Superweak Model Research Articles

The phase difference between K L → π+π− and K S → π+π− decay amplitudes

The phase difference between the K L → π + π − and K S → π + π − decay amplitudes has been measured by observing the time dependence of the π +π − decay intensity from an initial K° (strangeness = +1) state. The phase difference φ/ +− is found to be 41° ± 12° for a K L − K S mass difference Δm/ h ̵ = 0.526 × 10 10 sec − . The error includes statistical and systematic uncertainties. The phase φ +− is strongly correlated to the value adopted for Δm/ h ̵ . The present uncertainty on Δm/ h ̵ increases our error on φ +− from 12° to 15°. The result is in agreement with the prediction of the ‘superweak model’ of CP violation.

Observation of time-dependent K S and K L interference in the π +π − decay channel from an initial K 0 state

The phase ϕ +− between the amplitudes K L→ π + π − and K S→ π + π − has been measured. The result is 46 0 ± ± 15 0 for a K L - K S mass difference Δm/ h ̵ = (0.526±0.20) × 10 10 s −1 , in good agreement with the “superweak model” of Wolfenstein which predicts ϕ +− SW = 42.6 0 ± 1.0 0.

η+− phase, Re ϵ and the superweak model

The determination of the regeneration phase and of the ΔS − ΔQ violating parameter of the foregoing letters together with previous experiments yield new values for the ν +− phase and Reϵ. These are in substantial agreement with the predictions of the superweak model.