Triple-product asymmetry in the radiative two-pion tau decay

Abstract

Abstract In this work, we perform a detailed study of the τ − → π − π 0 γν decay process within the resonance chiral theory. We pay special attention to the triple-product asymmetry in the τ − → π − π 0 γν process. The minimal resonance chiral Lagrangian and the odd-intrinsic parity resonance operators are simultaneously included to calculate the decay amplitudes. Various invariant-mass distributions in the π − π 0, π − γ and π 0 γ systems are studied and they reveal different resonance dynamics. We further predict the intriguing nonzero triple-product asymmetry distributions, which may provide useful guidelines for future experimental measurements conducted at the Belle-II and super tau-charm facilities.

Keywords

• Chiral Lagrangian
• Effective Field Theories of QCD
• Semi-Leptonic Decays