Analysis of localized CP asymmetry in ${\bar{B}}_s^0\to {\pi }^{+}{\pi }^{-}{\pi }^0(K^0)$

Abstract

An investigation about localized CP asymmetries for the processes of ${\bar{B}}_s^0\to {\pi }^{+}{\pi }^{-}{\pi }^0(K^0)$ is presented in this paper. The innovation of this paper is that there is a consideration of three-particle ${\rho }^0(770)$, $\omega (782)$ and $\varphi (1020)$ interferences effect. Generally, $\omega (782)$ and $\varphi (1020)$ both can decay into ${\pi }^{+}{\pi }^{-}$ pair where can cause extremely small contribution from isospin symmetry breaking. Nevertheless, our analysis shows that ${\bar{B}}_s^0\to {\pi }^{+}{\pi }^{-}{\pi }^0(K^0)$ decay process can bring differential CP asymmetry about $65\%$ ($36\%$) because of isospin symmetry breaking. To better compared with the data from experimental in the future, we integrate CP asymmetry over the invariant mass and obtain localized CP asymmetry value for the decay ${\bar{B}}_s^0\to {\pi }^{+}{\pi }^{-}{\pi }^0(K^0)$. We find that there is an evident signal about CP asymmetry at invariant mass value $m({\pi }^{+}{\pi }^{-})$ below the mass of $\rho (770{)}^0$ with the decay ${\bar{B}}_s^0\to {\pi }^{+}{\pi }^{-}{\pi }^0$.