Abstract
Using a data sample corresponding to an integrated luminosity of collected at a center-of-mass energy by the BESIII detector, the decay is observed for the first time. The branching fraction is measured to be with a significance of , where the first and second uncertainties are statistical and systematic, respectively. An angular analysis reveals that the and mesons from the decay are transversely polarized. The 95% confidence level upper limit on longitudinal polarization fraction is set to be less than 0.24, which is inconsistent with current theoretical expectations and challenges our understanding of the underlying dynamics in charm meson decays.
- Received 5 August 2021
- Accepted 14 December 2021
DOI:https://doi.org/10.1103/PhysRevLett.128.011803
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