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PARAMETERS FOR ${{\mathit K}_S^0}$ $\rightarrow$ 3 ${{\mathit \pi}}$ DECAY

Im($\eta _{+−0}$) = Im(A( ${{\mathit K}_S^0}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ , $\mathit CP$-violating) $/$ A( ${{\mathit K}_L^0}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ ))

INSPIRE   PDGID:

S012E+

VALUE EVTS DOCUMENT ID TECN  COMMENT $-0.002$ $\pm0.009$ ${}^{+0.002}_{-0.001}$ 500k 1 ADLER 1997 B CPLR • • We do not use the following data for averages, fits, limits, etc. • • $-0.002$ $\pm0.018$ $\pm0.003$ 137k 2 ADLER 1996 D CPLR Sup. by ADLER 1997B $-0.015$ $\pm0.017$ $\pm0.025$ 272k 3 ZOU 1994 SPEC 1  ADLER 1997B also find Re($\eta _{+−0}$) = $-0.002$ $\pm0.007$ ${}^{+0.004}_{-0.001}$. See also ANGELOPOULOS 1998C. 2  The ADLER 1996D fit also yields Re($\eta _{+−0}$) = $0.006$ $\pm0.013$ $\pm0.001$ with a correlation $+0.66$ between real and imaginary parts. Their results correspond to $\vert \eta _{+−0}\vert <0.037$ with 90$\%$ CL. 3  ZOU 1994 use theoretical constraint Re($\eta _{+−0}$) = Re($\epsilon $) = $0.0016$. Without this constraint they find Im($\eta _{+−0}$) = $0.019$ $\pm0.061$ and Re($\eta _{+−0}$) = $0.019$ $\pm0.027$.

Conservation Laws:

$\mathit CP$ INVARIANCE

References:

ADLER 1997B PL B407 193 CPLEAR Results on the $\mathit CP$ Parameters of Neutral Kaons Decaying to ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ ADLER 1996D PL B370 167 Search for $\mathit CP$ Violation in the Decay of Neutral Kaons to ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$ ZOU 1994 PL B329 519 Search for $\mathit CP$ Violation in the Decay ${{\mathit K}_S^0}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{0}}$

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