Measurement of the charm-mixing parameter $y_{CP}$ in $D^{0}\to K^{0}_{S}\omega$ decays at Belle

TL;DR

This paper presents the first measurement of the charm-mixing parameter y_{CP} in D^{0} decays to a CP-odd final state using the full Belle dataset, providing insights into charm mixing phenomena.

Contribution

It reports the first measurement of y_{CP} in D^{0} to K^{0}_{S}ω decays, utilizing the complete Belle dataset at or near the Υ(4S) energy.

Findings

Measured y_{CP} = (0.96 ± 0.91 ± 0.61 +0.17/-0.00)%

First measurement of y_{CP} in this decay mode

Results consistent with no charm mixing within uncertainties.

Abstract

We report the first measurement of the charm-mixing parameter $y_{CP}$ in $D^{0}$ decays to the $CP$-odd final state $K^{0}_{S}\omega$. The study uses the full Belle $e^{+}e^-$ annihilation data sample of $976\rm~ fb^{-1}$ taken at or near the $\Upsilon(4S)$ centre-of-mass energy. We find $y_{CP} = (0.96 \pm 0.91 \pm 0.61 {}^{+0.17}_{-0.00})\%$, where the first uncertainty is statistical, the second is systematic due to event selection and background, and the last is due to possible presence of $CP$-even decays in the data sample.