${{\mathit D}^{0}}$ TESTS OF LOCAL $\mathit CP$-VIOLATION ($\mathit CPV$)

We list model-independent searches for local $\mathit CP$ violation in phase-space distributions of multi-body decays.
Most of these searches divide phase space (Dalitz plot for 3-body decays, five-dimensional equivalent for 4-body decays) into bins, and perform a ${{\mathit \chi}^{2}}$ test comparing normalised yields ${{\mathit N}_{{i}}}$, ${{\overline{\mathit N}}_{{i}}}$ in $\mathit CP$-conjugate bin pairs ${{\mathit i}}$: ${{\mathit \chi}^{2}}$ = ${{\mathit \Sigma}_{{i}}}({{\mathit N}_{{i}}}$ $−$ ${{\mathit \alpha}}{{\overline{\mathit N}}_{{i}}})/{{\mathit \sigma}}({{\mathit N}_{{i}}}−{{\mathit \alpha}}{{\overline{\mathit N}}_{{i}}}$). The factor ${{\mathit \alpha}}$ = (${{\mathit \Sigma}_{{i}}}{{\mathit N}_{{i}}})/({{\mathit \Sigma}_{{i}}}{{\overline{\mathit N}}_{{i}}}$) removes the dependence on phase-space-integrated rate asymmetries. The result is used to obtain the probability (p-value) to obtain the measured ${{\mathit \chi}^{2}}$ or larger under the assumption of CP conservation [AUBERT 2008AO, BEDIAGA 2009 ]. Alternative methods obtain p-values from other test variables based on unbinned analyses [WILLIAMS 2011 , AAIJ 2014C]. Results can be combined using Fisher's method [MOSTELLER 1948 ].

Local $\mathit CPV$ in ${{\mathit D}^{0}}$, ${{\overline{\mathit D}}^{0}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit K}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$

INSPIRE   PDGID:
S032L05
VALUE (%) EVTS DOCUMENT ID TECN  COMMENT
$\bf{9.1}$ 57k
AAIJ
2013BR
 LHCB ${{\mathit \chi}^{2}}$
Conservation Laws:
$\mathit CP$ INVARIANCE
References:
AAIJ 2013BR
PL B726 623 Model-Independent Search for $\mathit CP$ Violation in ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit K}^{+}}{{\mathit \pi}^{-}}{{\mathit \pi}^{+}}$ and ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit \pi}^{-}}{{\mathit \pi}^{+}}{{\mathit \pi}^{+}}{{\mathit \pi}^{-}}$ Decays