Abstract
We measure the branching fraction of the decay using data collected with the Belle II detector. The data contain 387 million pairs produced in collisions at the resonance. We reconstruct decays from an analysis of the distributions of the energy and the helicity angle. We determine the branching fraction to be , in agreement with previous results. Our measurement improves the relative precision of the world average by more than a factor of two.
- Received 18 April 2024
- Accepted 22 May 2024
DOI:https://doi.org/10.1103/PhysRevD.109.L111103
Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society