CP violation in $B^{\pm} \rightarrow \pi^{\pm}\pi^{+}\pi^{-}$ in the region with low invariant mass of one $\pi^{+}\pi^{-}$ pair

TL;DR

This paper investigates the large localized CP asymmetries in B±→π±π+π− decays, attributing them to interference between scalar and vector resonances, and highlights the usefulness of Dalitz plot analysis for resonance identification.

Contribution

It proposes that interference between scalar and vector resonances explains localized CP asymmetries and emphasizes Dalitz plot analysis as a tool for detecting scalar resonances in three-body B decays.

Findings

Large CP asymmetries are localized in specific invariant mass regions.

Interference between scalar and ρ^0(770) resonances explains asymmetries.

Dalitz plot distributions can help identify scalar resonances.

Abstract

Recently, the large CP asymmetries in $B^\pm\to\pi^\pm\pi^+\pi^-$ decays were found by the LHCb Collaboration to localize in the region $m_{\pi^+\pi^-}^2<0.4 \text{GeV}^2$. We find such large localized CP asymmetries may be due to the interference between a light scalar and $\rho^0(770)$ intermediate resonances. Consequently, we argue that the distribution of CP asymmetries in the Dalitz plots of three-body B decays could be very helpful for identifying the presence of the scalar resonance.