CP Violation in τ Decays at SuperB & Belle II Experiments – like Finding Signs of Dark Matter

Abstract

BaBar has found $A_{\mathrm{CP}}({\tau }^{-}\to \nu K_S{\pi }^{-}[\ge {\pi }^0\left]\right)=(-0.36\pm 0.23\pm 0.11)\text{\%}$ with 2.8 σ difference with SM prediction $A_{\mathrm{CP}}({\tau }^{-}\to \nu K_S{\pi }^{-})=(0.36\pm 0.01)\text{\%}$ based on $K^0-{\overline{K}}^0$ oscillation. Four central points: (i) to establish both the ‘existence’ of New Dynamics (ND) and its ‘features’ in local CP asymmetries; (ii) to increase the number of final states to be probed; (iii) to emphasize correlations of CP violations between different final states; (iv) likewise for the correlations with $D^{\pm }$ final states. These measurements should be possible at SuperB & Belle II experiments.