Rescattering and electroweak penguin effects in determinations of the weak phase $\gamma$

TL;DR

This paper discusses how electroweak penguin and rescattering effects influence the measurement of the CKM phase gamma in B decays, proposing methods to control and mitigate these effects using SU(3) symmetry and alternative decay channels.

Contribution

It introduces a way to control electroweak penguin effects via SU(3) symmetry and explores the significance of rescattering effects on gamma determination, proposing alternative methods to reduce uncertainties.

Findings

Electroweak penguin effects can be related to tree amplitudes using SU(3) symmetry.

Rescattering effects can significantly impact gamma measurements from B+→Kπ decays.

Alternative decay channels can help eliminate rescattering effects in gamma determination.

Abstract

Determinations of the CKM phase $\gamma$ from weak nonleptonic $B$ decays are affected by electroweak (EW) penguins and rescattering effects. In this talk it is explained how the EW penguin effects can be controlled with the help of SU(3) symmetry, by relating them to tree-level amplitudes. The impact of the final-state interactions on the determination of $\gamma$ from $B^+\to K\pi$ decays is studied numerically, showing that they can be important. A few alternative methods are discussed which use additional decays to eliminate their effects.