Correlations of $C$ and $CP$ violation in $η\to π^0\ell^+\ell^-$ and $η'\to η\ell^+\ell^-$

• DOI: 10.48550/arxiv.2307.02533
• Publication Date: 2023-01-01
• Authors: Akdag, Hakan; Kubis, Bastian; Wirzba, Andreas
• Keywords: Nuclear Theory (nucl-th); High Energy Physics - Experiment (hep-ex); High Energy Physics - Phenomenology (hep-ph); FOS: Physical sciences

Based on recent progress in the systematic analysis of $C$ and $CP$ violation in the light-meson sector, we calculate the $C$-odd transition amplitudes $η\toπ^0\ell^+\ell^-$ and $η'\toη\ell^+\ell^-$. Focusing on long-distance contributions driven by the lowest-lying hadronic intermediate states, we work out the correlations between these beyond-the-Standard-Model signals and the Dalitz-plot asymmetries in $η\rightarrow π^0 π^+ π^-$ and $η' \rightarrow ηπ^+ π^- $, using dispersion theory.<br/>35 pages, 7 figures, 3 tables; v2: section 5 revised, discussion extended, version published in JHEP<br/>