We present a series of measurements based on K L,S→ π + π - and K L,S→π 0π 0 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 → π 0 π 0 (φ 00). We find the difference between the relative phases to be Δφ=φ 00-φ +- = (+ 0.39 ±0.50)°, and the deviation of φ +- from the superweak phase to be φ +- - φ SW=(+0.61±1.19)°; both results are consistent with CPT symmetry. In addition, we present new measurements of the K L-K S mass difference and K S lifetime: Δm = (5261±15)×10 6 ℏs -1 and τ S= (89.65±0.07)×10 -12 S.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)