Complementary CP violation induced by T -odd and T -even correlations

Abstract

In this Letter, we demonstrate that T-odd and T-even correlations, with T representing time reversal, when satisfying specific conditions, result, respectively, in cosine and sine strong phase dependencies of the corresponding CP violation. Additionally, we identify pairs of these CP violation observables in hadron decays depend on precisely the same strong phases within the helicity amplitude scheme. This complementarity could reduce the strong phase reliance in the study of CP violation while also mitigating the risk of suppressed CP violation due to exceptionally small strong phases. Moreover, our proposal holds broad application prospects in further investigating CP violation in baryon decays, which has recently been discovered in the LHCb experiment. Published by the American Physical Society 2025