FSI and rare B decays: B-->\pi\pi, \rho\rho

TL;DR

This paper proposes a final state interactions model based on soft rescattering to explain the differing strong interaction phases observed in B meson decays to pi pi and rho rho final states.

Contribution

It introduces a FSI model emphasizing soft rescattering of low mass states to account for phase differences in B decay channels.

Findings

Large strong phases in B_d→ππ decays explained by FSI.

Smaller phases in B_d→ρρ decays consistent with the model.

Supports the significance of soft rescattering in B decay dynamics.

Abstract

The final state interactions (FSI) model, in which soft rescattering of low mass intermediate states dominate, is suggested. It explains why the strong interaction phases are large in the $B_d\to\pi\pi$ channel and are considerably smaller in the $B_d\to\rho\rho$ one.