Improved measurement of time-dependent CP violation in B0 -> J/Psi pi0 decays

TL;DR

This paper presents improved measurements of time-dependent CP violation parameters in B0 -> J/Psi pi0 decays, using a large dataset from the Belle experiment, providing results consistent with the Standard Model.

Contribution

The study provides more precise measurements of CP violation parameters in B0 -> J/Psi pi0 decays, enhancing the understanding of CP violation in the B meson system.

Findings

Measured CP violation parameters consistent with Standard Model

Used 535 million B Bbar pairs from Belle detector

Achieved improved precision over previous measurements

Abstract

We report improved measurements of time-dependent CP violation parameters for $B^0(\bar{B}^0) \to J/\psi \pi^0$ decay. This analysis is based on 535 million $B\bar{B}$ pairs accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. From the distribution of proper time intervals between the two B decays, we obtain the following CP violation parameters $\mathcal{S}_{J/\psi \pi^0} = -0.65\pm0.21 (\rm{stat})\pm0.05 (\rm{syst})$ and $\mathcal{A}_{J/\psi \pi^0} = +0.08\pm0.16 (\rm{stat})\pm0.05 (\rm{syst})$, which are consistent with Standard Model expectations.