Measurement of CP violation parameters in $ \overline{K}^0\to \pi^+ \pi^- \pi^0 $ decays

A measurement of CP violation parameters in $\overline{K}^0\to \pi^+ \pi^- \pi^0$ decay at the CPLEAR experiment is presented. Tagging of neutral-kaon strangness at the production time and reconstruction of its lifetime enables a construction of lifetime-dependent decay asymmetry. A non-zero value of the asymmetry is a sign of CP violation in $\overline{K}^0\to \pi^+ \pi^- \pi^0 $ decay. The asymmetry is described by the CP violation parameter $\eta_{+-0}$. Due to insufficient amount of data, the analysis gives results compatible with zero, $\Re \eta_{+-0} = -0.0035\pm 0.0159 $stat. $ \pm 0.0048$syst., $\Im \eta_{+-0} = -0.0064\pm 0.0184$stat. $\pm 0.0037$syst. As an additional outcome of the analysis, the branching ratio of $K_S\to \pi^+ \pi^- \pi^0$ decay is measured for the first time, B($K_S\to \pi^+ \pi^- \pi^0$) = [6.4 + $\binom{+3.8}{-2.9} $stat. + $\binom{+2.4}{-2.0}$syst.$\pm$0.2 PDG] x 10$^{-7}$.