Probing CP violation in $B^0_s \rightarrow K^{0}_{\rm S} π^{+}π^{-}$ decays
Tim Gershon, Thomas Latham, Rafael Silva Coutinho
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6 pages, 2 figures. Presentation at the 37th International Conference on High Energy Physics (ICHEP 2014) held in Valencia, Spain (2nd to 9th July 2014)
The three-body charmless hadronic decay $B^0_s \rightarrow K^{0}_{\rm S} π^{+}π^{-}$ provides a number of novel possibilities to search for CP violation effects and test the Standard Model of particle physics. These include fits to the Dalitz-plot distributions of the decay-time-integrated final state, decay-time-dependent (but without initial state flavour tagging) fits to the Dalitz-plot distribution, as well as full decay-time-dependent and flavour tagged fits. The relative sensitivities of these different approaches are investigated.
The decays $K^{\ast}(892)\rightarrow K_{S,L}^{0}π$ can be used to study CP violation and CPT violation. The $K^{\ast}(892)$ (hereinafter referred to as $K^{\ast}$) meson can be produced via $J/ψ$ decays at BESIII. In this paper, we study CP violation and $K_S^0-K_L^0$ asymmetry in the $J/ψ$ decays involving the $K^{\ast}$ meson in the final states and obtain the following results \begin{align} {\mathcal A}_{CP}\left(J/ψ\rightarrow K^{\ast}f_{J/ψ}\rightarrow K^0_{S}πf_{J/ψ}\right)=\left(3.64\pm0.04\right)\times 10^{-3},\nonumber\\ {\mathcal A}_{CP}\left(J/ψ\rightarrow K^{\ast}f_{J/ψ}\rightarrow…
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The SM predicts zero value for {\bf CP} \& {\bf T} violation in the decays of $τ$ leptons -- except $τ^- \to νK_S [π^-/π^-π^0 ...]$. Our community could establish impact of New Dynamics (ND) in a {\bf CP} asymmetry in a semi-hadronic $τ$ transition and later in a second one. To be `practical', I suggest to our experimental colleagues to probe $τ^- \to ν\bar K^0 [π^-/π^-π^0/π^-η]$and $τ^- \to νK^-[π^0/π^+π^-/η]$. While I had mostly given comments about {\bf CP} violation in $τ$ transitions, some theorists have shown how ND models could produce {\bf CP} asymmetries; I will discuss these ones, al…
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