Studies of CP violation in B->J/psi K* decays

TL;DR

This study investigates CP violation in B->J/psi K* decays through angular analysis, finding no evidence for direct CP violation and results consistent with Standard Model predictions.

Contribution

It provides the first detailed angular analysis of CP violation in B->J/psi K* decays using a large data sample, including measurements of decay amplitudes and CP-violating parameters.

Findings

No evidence for direct CP violation.

Results consistent with Standard Model null predictions.

Measured CP-violating parameters with large uncertainties.

Abstract

CP violation in $B\to J/\psi K^*$ decays is studied using an angular analysis in a data sample of 253 fb$^{-1}$ recorded with the Belle detector at the KEKB $e^+e^-$ collider. The flavor separated measurements of the decay amplitudes indicate no evidence for direct CP violation. T-odd CP violation is studied using the asymmetries in triple product correlations, and the results are consistent with the Standard Model null predictions. The time-dependent angular analysis gives the following values of CP violating parameters: $\sin 2\phi_1 = 0.24 \pm 0.31 \pm 0.05$ and $\cos 2\phi_1 = 0.56 \pm 0.79 \pm 0.11$.