Coupled-Channel Final-State Interactions through Reggeon Exchange for D(B) --> \pi \pi, K \bar{K}

TL;DR

This paper investigates how coupled-channel final-state interactions, modeled via Reggeon exchange, significantly influence decay amplitudes and phases in D and B meson decays into pion and kaon pairs, surpassing previous quasi-elastic approximations.

Contribution

It introduces a Regge-based framework to incorporate coupled-channel effects in D and B meson decays, highlighting their impact on decay phases and amplitudes.

Findings

Coupled-channel effects alter decay amplitude calculations.

Inelastic transitions significantly affect phase shifts.

Regge framework improves understanding of final-state interactions.

Abstract

Coupled-channel final-state-interaction effects for D and B weak decays into \pi \pi and K \bar{K} are discussed in a Regge framework. It is found that the inclusion of coupled-channel effects significantly affects the results obtained previously in a quasi-elastic approximation. It is also shown that in the isospin I=0 channel the inelastic final-state transitions (\pi \pi)_{I=0} --> (K \bar{K})_{I=0} dramatically influence the phase of the B^0 --> (K \bar{K})_{I=0} amplitude.