Abstract
We report the first evidence for isospin violation in and the first measurement of the difference of asymmetries between and . This analysis is based on the data sample containing pairs that was collected with the Belle detector at the KEKB energy-asymmetric collider. We find evidence for the isospin violation with a significance of , , where the third uncertainty is due to the uncertainty on the fraction of to production in decays. The measured value is consistent with predictions of the standard model. The result for the difference of asymmetries is , consistent with zero. The measured branching fractions and asymmetries for charged and neutral meson decays are the most precise to date. We also calculate the ratio of branching fractions of to .
- Received 29 June 2017
DOI:https://doi.org/10.1103/PhysRevLett.119.191802
© 2017 American Physical Society