Observation of Interference Between Positive-Pion Negative-Pion Amplitudes from K-L Decay and Coherent Regeneration

摘要

A spark chamber - magnetic spectrometer search for interference between positive-pion negative-pion decay amplitudes produced in free K-L decay, in apparent violation of CP invariance in the weak interactions, and from coherent regeneration was performed. Using diffuse beryllium regenerators of different mean densities, evidence was found for maximal constructive interference, independent of the K-S - K-L mass difference. Additional data using a solid beryllium regenerator provides good evidence that the magnitude of the mass difference lies in the interval 0.4