Experimental study of Ko → π+ π− πo decays and search for CP violation

Abstract The time distribution of 180 uniquely identified π + π − π o decays of the K o meson between 0.04 and 20 K S o lifetimes has been studied. We find that the ratio η + − o of the K S o → π + π − π o to the K L o → π + π − π o amplitude is consistent with no CP violation. Our results confine η + −o to ∼0 η + −o η + −o . If we set Re η −o = 0, we obtain Im η + −o = 0.37 −-.34 +0.47 . If in addition we use the known value of Γ (K L o → π + π − π o ) we obtain Im η = −0.23 −0.25 +0.31 . Without these restrictions, a more accurate determination of η + −o can only be made, with the present statistics, by a combination of K o and K o data. Assuming η + −o = 0, we find Γ (K L o → π + π − π o = (2.35 ± 0.20) × 10 6 s −1 .