MAY 01, 1999
Exquisitely careful comparison of different decay charge states tells us that the kaon’s violation of CP symmetry is, at least in part, attributable to standard‐model mechanisms rather than to some hypothetical superweak interaction.
A long‐awaited experimental result, recently announced by the KTeV collaboration at the Fermilab Tevatron, does much to clarify the mechanism by which the decay of the neutral K mesons violates CP symmetry. Despite 35 years of painstaking investigation since the discovery of CP‐violating decay by James Cronin, Val Fitch, James Christenson, and René Turlay, the important issue of what causes this asymmetry in nature had remained disturbingly unsettled. CP denotes the combined operation of charge conjugation (C), that is to say, the replacement of particles by their antiparticles, and parity inversion (P). After the rude overthrow of parity conservation in 1957, CP offered a refuge for believers in mirror symmetry, but only until the next rude overthrow, by Fitch, Cronin and company, in 1964.
© 1999. American Institute of Physics
