# $\Delta \boldsymbol A_{CP}$ = $\boldsymbol A_{CP}$( ${{\boldsymbol K}^{+}}{{\boldsymbol K}^{-}}$ ) $−$ $\boldsymbol A_{CP}$( ${{\boldsymbol \pi}^{+}}{{\boldsymbol \pi}^{-}}$ ) INSPIRE search

$\mathit CP$ violation in these modes can come from the decay amplitudes (direct) and/or from mixing or interference of mixing and decay (indirect). The difference $\Delta \mathit A_{CP}$ is primarily sensitive to the direct component, and only retains a second-order dependence on the indirect component for measurements where the mean decay time of the ${{\mathit K}^{+}}{{\mathit K}^{-}}$ and ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ samples are not identical. The results below are averaged assuming the indirect component can be neglected.
VALUE (%) EVTS DOCUMENT ID TECN  COMMENT
$\bf{ -0.161 \pm0.029 }$ OUR AVERAGE
$-0.154$ $\pm0.029$ 53M,17M
 2019 D
LHCB Time-integrated
$-0.62$ $\pm0.21$ $\pm0.10$
 2012 O
CDF Time-integrated
• • • We do not use the following data for averages, fits, limits, etc. • • •
$-0.10$ $\pm0.08$ $\pm0.03$ 6.5M,2.2M
 2016 D
LHCB See AAIJ 2019D
$0.14$ $\pm0.16$ $\pm0.08$ 2.2M,0.8M
 2014 AK
LHCB See AAIJ 2019D
$0.49$ $\pm0.30$ $\pm0.14$ 0.56M,0.22M
LHCB See AAIJ 2014AK
$-0.82$ $\pm0.21$ $\pm0.11$ 1.4M,0.4M
 2012 G
LHCB See AAIJ 2016D
$-0.46$ $\pm0.31$ $\pm0.12$
 2012 B
CDF
$0.24$ $\pm0.62$ $\pm0.26$ 1
 2008 M
BABR Time-integrated
$-0.86$ $\pm0.60$ $\pm0.07$ 120k
 2008
BELL Time-integrated
1  Calculated from the AUBERT 2008M values of $\mathit A_{CP}$( ${{\mathit K}^{+}}{{\mathit K}^{-}}$ ) and $\mathit A_{CP}$( ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ ). The systematic error here combines the systematic errors in quadrature, and therefore somewhat over-estimates it.
Conservation Laws:
 $\mathit CP$ VIOLATION OBSERVED
References:
 AAIJ 2019D
arXiv:1903.08726
 AAIJ 2016D
PRL 116 191601 Measurement of the Difference of Time-Integrated $\mathit CP$ Asymmetries in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit K}^{+}}$ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}$ Decays
 AAIJ 2014AK
JHEP 1407 041 Measurement of $\mathit CP$ Asymmetry in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit K}^{+}}$ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}$ Decays
PL B723 33 Search for Direct $\mathit CP$ Violation in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit h}^{-}}{{\mathit h}^{+}}$ Modes using Semileptonic ${{\mathit B}}$ Decays
PRL 108 111602 Evidence for $\mathit CP$ Violation in Time-Integrated ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit h}^{-}}{{\mathit h}^{+}}$ Decay Rates
PRL 109 111801 Measurement of the Difference in $\mathit CP$-Violating Asymmetries in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}$ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Decays at CDF
PR D85 012009 Measurement of $\mathit CP$-Violating Asymmetries in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}$ Decays at CDF
PRL 100 061803 Search for $\mathit CP$ Violation in the Decays D0-->K-K+ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}$
PL B670 190 Search for a $\mathit CP$ Asymmetry in Cabibbo-Suppressed ${{\mathit D}^{0}}$ Decays