Studying New Physics Amplitudes in Charmless B_s Decays

TL;DR

This paper introduces a flavour SU(3)-based method to identify and extract New Physics amplitudes in charmless $B_s$ decays by analyzing time-dependent CP asymmetries and related decay modes, accounting for SU(3) breaking effects.

Contribution

It proposes a novel SU(3) symmetry approach to isolate and measure New Physics contributions in $B_s$ decays, including handling SU(3) breaking uncertainties.

Findings

Method can determine NP amplitude magnitude and phases.

Reduces SU(3) breaking uncertainties using amplitude ratios.

Applicable to decays into neutral vector mesons.

Abstract

A method based on flavour SU(3) is proposed for identifying and extracting New Physics (NP) amplitudes in charmless $\Delta S=1$ $B_s$ decays using time-dependent CP asymmetries in these decays and in flavour SU(3) related $\Delta S=0$ decays. For illustration, we assume a hierarchy, $\sim 1: \lambda : \lambda^2$ ($\lambda=0.2$), between a dominant $\Delta S=1$ penguin amplitude, a NP amplitude and a Standard Model amplitude with weak phase $\gamma$. An uncertainty from SU(3) breaking corrections, reduced by using ratios of hadronic amplitudes, is further suppressed by a factor $\lambda$. We discuss examples for pairs of decays into two neutral vector mesons, $B_s\to\phi\phi, B_s\to\phi \bar K^{*0}$ and $B_s\to K^{*0}\bar K^{*0}, B^0\to K^{*0}\bar K^{*0}$, where the magnitude of the NP amplitude, its weak and strong phases can be determined.