U-spin sum rules for CP asymmetries of three-body charmed baryon decays

摘要

Triggered by a recent LHCb measurement and prospects for Belle II, we derive U -spin symmetry relations between integrated C P asymmetries of three-body Λ c + and Ξ c + decays. The sum rules read A C P ( Λ c + → p K ? K + ) + A C P ( Ξ c + → Σ + π ? π + ) = 0 , A C P ( Λ c + → p π ? π + ) + A C P ( Ξ c + → Σ + K ? K + ) = 0 , and A C P ( Λ c + → Σ + π ? K + ) + A C P ( Ξ c + → p K ? π + ) = 0 . No such U -spin sum rule exists between A C P ( Λ c + → p K ? K + ) and A C P ( Λ c + → p π ? π + ) . All of these sum rules are associated with a complete interchange of d and s quarks. Furthermore, there are no U -spin C P asymmetry sum rules which hold to first order U -spin breaking.