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$\mathit CP$ VIOLATION TESTS IN ${{\mathit K}^{\pm}}$ DECAYS

$\Delta $ = ($\Gamma\mathrm {({{\mathit K}^{+}})}$ $−$ $\Gamma\mathrm {({{\mathit K}^{-}})}$) $/$ ($\Gamma\mathrm {({{\mathit K}^{+}})}$ + $\Gamma\mathrm {({{\mathit K}^{-}})}$)

$\Delta $( ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{0}}{{\mathit \gamma}}$ ) RATE DIFFERENCE/SUM

INSPIRE   PDGID:

S010CPG

VALUE ($ 10^{-3} $) EVTS DOCUMENT ID TECN CHG  COMMENT $\bf{ }$ OUR AVERAGE $0.0$ $\pm1.0$ $\pm0.6$ 1M 1 BATLEY 2010 A NA48 $4$ $\pm29$ 2461 SMITH 1976 WIRE $\pm{}$ E$_{{{\mathit \pi}}}$ 55$-$90 MeV $5$ $\pm20$ 4000 ABRAMS 1973 B ASPK $\pm{}$ E$_{{{\mathit \pi}}}$ 51$-$100 MeV 1  This value implies the upper bound for this asymmetry $1.5 \times 10^{-3}$ at 90$\%$ CL.

Conservation Laws:

$\mathit CP$ INVARIANCE

References:

BATLEY 2010A EPJ C68 75 Measurement of the Direct Emission and Interference Terms and Search for $\mathit CP$ Violation in the Decay ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{0}}{{\mathit \gamma}}$ SMITH 1976 NP B109 173 A Search for $\mathit CP$ Violation in ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{0}}{{\mathit \gamma}}$ Decays ABRAMS 1973B PRL 30 500 Test of $\mathit CP$ Noninvariance in the Decay ${{\mathit K}^{\pm}}$ $\rightarrow$ ${{\mathit \pi}^{\pm}}{{\mathit \pi}^{0}}{{\mathit \gamma}}$

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