Experimental study of the time-dependent rate of K0 → π+π−π0

Abstract The time-dependence of the decay rate of initially pure K 0 into the final state ( π + π − π 0 ) has been studied in search for the decay k S 0 → π + π − π 0 . No evidence is found in a sample of 384 observed events. The ratio of the CP -violating K S 0 amplitude and the K L 0 amplitude is η +−0 = (0.13 −0.20 +0.17 ) + i(0.17 −0.26 +0.27 ); the ratio of the CP -conserving K S 0 amplitude and the K L 0 amplitude is ∣ ϱ ∣ 0 → π + π − π 0 matrix element is found to be a +−0 = −0.31 ± 0.03.