Using U Spin to Extract gamma from Charmless B -> PPP Decays

TL;DR

This paper adapts a U-spin based method to extract the CP-violating phase gamma from charmless three-body B decays, potentially reducing U-spin breaking effects through Dalitz plot averaging.

Contribution

It introduces a novel application of U-spin symmetry to three-body B decays, avoiding isobar analyses and enabling gamma measurement via Dalitz plot analysis.

Findings

Potential reduction of U-spin breaking effects

Feasibility of measuring gamma without isobar analysis

Testable predictions using CP asymmetries and branching ratios

Abstract

Some years ago, a method was proposed for measuring the CP-violating phase gamma using pairs of two-body decays that are related by U-spin reflection (d <-> s). In this paper we adapt this method to charmless B -> PPP decays. Time-dependent Dalitz-plot analyses of these three-body decays are required for the measurement of the mixing-induced CP asymmetries. However, isobar analyses of the decay amplitudes are not necessary. A potential advantage of using three-body decays is that the effects of U-spin breaking may be reduced by averaging over the Dalitz plot. This can be tested independently using the measurements of direct CP asymmetries and branching ratios in three-body charged B decays.