Evidence for Large Direct CP Violation in B+-=>rho(770)0K+- from Analysis of the Three-Body Charmless B+-=>K+-pi+-pi-+ Decay

TL;DR

This paper presents evidence of large direct CP violation in charged B meson decays, specifically in B+-=>rho(770)0K+-, based on a Dalitz analysis of three-body charmless decay data from the Belle experiment.

Contribution

First observation of B+=>f_2(1270)K+ decay and evidence for large direct CP violation in B+-=>rho(770)0K+- decay in a comprehensive Dalitz analysis.

Findings

First observation of B+=>f_2(1270)K+ decay

Evidence for large direct CP violation in B+-=>rho(770)0K+-

Analysis based on 386 million BBbar pairs at Belle

Abstract

We report results on a Dalitz analysis of three-body charmless B+-=>K+-pi+-pi-+ decay including searches for direct CP violation. We report the first observation of the decay B+=>f_2(1270)K+ with a statistical significance above 6sigma. We also observe 3.9sigma evidence for large direct CP violation in the B+-=>rho(770)0K+- channel. This is the first evidence for CP violation in a charged meson decay. The results are obtained with a data sample that contains 386 million BBbar pairs collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider.