# $\boldsymbol A_{\boldsymbol CPT}({{\boldsymbol K}^{\mp}}{{\boldsymbol \pi}^{\pm}}$) in ${{\boldsymbol D}^{0}}$ $\rightarrow$ ${{\boldsymbol K}^{-}}{{\boldsymbol \pi}^{+}}$ , ${{\overline{\boldsymbol D}}^{0}}$ $\rightarrow$ ${{\boldsymbol K}^{+}}{{\boldsymbol \pi}^{-}}$ INSPIRE search

$\mathit A_{\mathit CPT}$(t) is defined in terms of the time-dependent decay probabilities ${{\mathit P}}$( ${{\mathit D}^{0}}$ $\rightarrow$ ${{\mathit K}^{-}}{{\mathit \pi}^{+}}$ ) and ${{\overline{\mathit P}}}$( ${{\overline{\mathit D}}^{0}}$ $\rightarrow$ ${{\mathit K}^{+}}{{\mathit \pi}^{-}}$ ) by $\mathit A_{\mathit CPT}$(t) = (${{\overline{\mathit P}}}−{{\mathit P}})/({{\overline{\mathit P}}}$ + ${{\mathit P}}$). For small mixing parameters x${}\equiv\Delta \mathit m/\Gamma$ and y${}\equiv\Delta \Gamma /2\Gamma$ (as is the case), and times t, $\mathit A_{\mathit CPT}$(t) reduces to [~y $\mathit Re$~$\xi$ - x $\mathit Im$~$\xi$~]~$\Gamma$t, where $\xi$ is the $\mathit CPT$-violating parameter.

The following is actually y $\mathit Re$~$\xi$ - x $\mathit Im$~$\xi$.

VALUE DOCUMENT ID TECN  COMMENT
$0.0083$ $\pm0.0065$ $\pm0.0041$
 2003 B
FOCS $\gamma$ nucleus, ${{\overline{\mathit E}}}_{\gamma }\approx{}$180 GeV
Conservation Laws:
 $\mathit CPT$ INVARIANCE
References:
PL B556 7 Charm System Tests of $\mathit CPT$ and Lorentz Invariance with FOCUS