We report final measurements of direct $CP$-violating asymmetries in charmless decays of neutral bottom hadrons to pairs of charged hadrons with the upgraded Collider Detector at the Fermilab Tevatron. Using the complete $\sqrt{s}=1.96\mathrm{TeV}$ proton-antiproton collisions data set, corresponding to $9.3{\mathrm{fb}}^{-1}$ of integrated luminosity, we measure $\mathcal{A}({\mathrm{\Lambda }}_b^0\to p{\pi }^{-})=+0.06\pm 0.07(\text{stat})\pm 0.03(\text{syst})$ and $\mathcal{A}({\mathrm{\Lambda }}_b^0\to p{K}^{-})=-0.10\pm 0.08(\text{stat})\pm 0.04(\text{syst})$, compatible with no asymmetry. In addition we measure the $CP$-violating asymmetries in $B_s^0\to K^{-}{\pi }^{+}$ and $B^0\to K^{+}{\pi }^{-}$ decays to be $\mathcal{A}(B_s^0\to K^{-}{\pi }^{+})=+0.22\pm 0.07(\text{stat})\pm 0.02(\text{syst})$ and $\mathcal{A}(B^0\to K^{+}{\pi }^{-})=-0.083\pm 0.013(\text{stat})\pm 0.004(\text{syst})$, respectively, which are significantly different from zero and consistent with current world averages.

• Received 21 March 2014

DOI:https://doi.org/10.1103/PhysRevLett.113.242001