Abstract
A sizable right-handed photon polarization in is a clear signal for new physics. In this Letter, we point out that the photon helicity in can be unambiguously extracted by combining the measurements in and the Cabibbo-favored decay. We propose a ratio of up-down asymmetries in to quantify the hadronic effects. A method for measuring, in experiment, the involved partial decay widths in the ratio is discussed, and experimental facilities like BESIII, Belle-II and LHCb are likely to measure this ratio. We also give the angular distribution that is useful for extracting the photon polarization in the presence of different kaon resonances.
- Received 14 October 2019
- Revised 2 May 2020
- Accepted 7 July 2020
DOI:https://doi.org/10.1103/PhysRevLett.125.051802
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