Evidence for Direct CP Violation from Dalitz-plot analysis of B+/- -> K+/- pi+/- pi-/+

TL;DR

This paper presents a Dalitz-plot analysis of B+/- decays to K+/- pi+/- pi-/+ revealing evidence of direct CP violation in specific decay channels, based on a large dataset collected by BaBar.

Contribution

It provides the first evidence of direct CP violation in B+ -> rho0(770) K+/- decays through detailed Dalitz-plot analysis.

Findings

Evidence for direct CP violation in B+ -> rho0(770) K+/-

Measured CP asymmetry A_CP = (+44 +/- 10 +/- 4 +5,-13)%

Quantified branching fractions for decay contributions

Abstract

We report a Dalitz-plot analysis of the charmless hadronic decays of charged B mesons to the final state K+/- pi+/- pi-/+. Using a sample of 383.2 +/- 4.2 million BBbar pairs collected by the BaBar detector, we measure CP-averaged branching fractions and direct CP asymmetries for intermediate resonant and nonresonant contributions. We find evidence for direct CP violation in the decay B+ -> rho0(770) K+, with a CP violation parameter A_CP = (+44 +/- 10 +/- 4 +5,-13)%.