We present a series of measurements based on KL,S→ π+ π- and K L,S→π0π0 decays collected in 1996-1997 by the KTeV experiment (E832) at Fermilab. We compare these four K→ππ decay rates to measure the direct CP violation parameter Re(ε′/ε) = (20.7±2.8)×10-4. We also test CPT symmetry by measuring the relative phase between the CP violating and CP conserving decay amplitudes for K → π+ π- (φ+-) and for K → π0 π0 (φ00). We find the difference between the relative phases to be Δφ=φ00-φ+- = (+ 0.39 ±0.50)°, and the deviation of φ+- from the superweak phase to be φ+- - φSW=(+0.61±1.19)°; both results are consistent with CPT symmetry. In addition, we present new measurements of the KL-KS mass difference and KS lifetime: Δm = (5261±15)×106 ℏs-1 and τS= (89.65±0.07)×10-12 S.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)