Measurement of Polarization and Triple-Product Correlations in B -> phi K^* Decays

TL;DR

This paper reports measurements of decay amplitudes and triple-product correlations in B -> phi K^* decays, providing insights into polarization states and CP violation with data from the Belle detector.

Contribution

First measurement of decay amplitudes and triple-product correlations in B -> phi K^* decays using Belle data, testing CP violation and polarization.

Findings

Longitudinal polarization amplitudes around 0.45-0.52

Triple-product asymmetries consistent with zero

Results constrain models of CP violation in B decays

Abstract

We present measurements of decay amplitudes and triple-product correlations in B -> phi K^* decays based on 253 fb^-1 of data recorded at the Upsilon(4S) resonance with the Belle detector at the KEKB e^+ e^- storage ring. The decay amplitudes for the three different helicity states are determined from the angular distributions of final state particles. The longitudinal polarization amplitudes are found to be 0.45 +- 0.05 +- 0.02 for B^0 -> phi K^{*0} and 0.52 +- 0.08 +- 0.03 for B^+ -> phi K^{*+} decays. CP- and T-odd CP-violating triple-product asymmetries are measured to be consistent with zero.