Search for CP violation in the K 0 →π + π − π 0 decay

In a total of 1.8·106 photograms of the 180 litre xenon bubble chamber exposed to a K+ beam with 0.85 GeV/c momentum, 409 identified K0→π+π−π0 decays were selected and the ratio of theCP-violating to theCP-conserving amplitudes η+−0=A(K S o →π+π−π0)/A (K L 0 →π+π−π0) was measured. The results are: η+−0=(−0.002 ±, 0.23) +i(−0.14±0.35), and assuming Re η+−0=0, |η+−0|2<0.2 and Г(K S 0 →π+π−π0)/Г(K S 0 →all)<5.5·10−5 at the 90% c.l. Moreover, combining the present results with those of a previous experiment performed and analysed in a similar way, corresponding to a total of 601 events, η+−0=(0.05±0.17)+i(0.15±0.33);|η+−0|2<0.23 and Г(K S 0 → π+π−π0)/Г(K S 0 →all)<4.9·10−5 were obtained.