Search for CP Violation in the Decay D+/- -> Ks pi+/-

Abstract

We report on a search for CP violation in the decay $ D^\pm \to K^0_{\scriptscriptstyle S} π^\pm $ using a data set corresponding to an integrated luminosity of $ 469\,\,fb^{-1} $ collected with the \slshape B\kern-0.1em{\smaller A}\kern-0.1em B\kern-0.1em{\smaller A\kern-0.2em R} detector at the PEP-II asymmetric energy $e^+e^-$ storage rings. The CPviolating decay rate asymmetry $A_{CP}$ is determined to be $(-0.44 \pm 0.13 \mathrm{(stat)} \pm 0.10 \mathrm{(syst)})%$, consistent with zero at 2.7 $σ$ and with the standard model prediction of $(-0.332 \pm 0.006)%$. This is currently the most precise measurement of this parameter.