Correlations of C and CP violation in η → π0ℓ+ℓ− and η′ → ηℓ+ℓ−

Abstract

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 → π0ℓ+ℓ− and η′ → ηℓ+ℓ−. 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 → π0π+π− and η′ → ηπ+π−, using dispersion theory.