Pursuit of new physics within the $$\Lambda _c\rightarrow \Delta K$$ decays

Abstract

AbstractWe point out the CP asymmetry in the chain decay of $$\Lambda _c^+\rightarrow \Delta ^+K(t)(\rightarrow \pi ^+\pi ^-)$$ Λ c + → Δ + K ( t ) ( → π + π - ) is determined by the branching fractions of $$\Lambda ^+_c\rightarrow \Delta ^{++} K^-$$ Λ c + → Δ + + K - , $$\Lambda ^+_c\rightarrow \Delta ^{+} K^0_{S,L}$$ Λ c + → Δ + K S , L 0 and $$\Lambda ^+_c\rightarrow \Delta ^{0} K^+$$ Λ c + → Δ 0 K + modes under the isospin symmetry. The ambiguities from loop-induced quantities and $$SU(3)_F$$ S U ( 3 ) F breaking hadronic effects are avoided. Once the CP asymmetry in the $$\Lambda _c^+$$ Λ c + decays into $$\Delta ^+$$ Δ + and neutral kaons is confirmed by experiments, we can check if it is beyond the Standard Model, or verify the CP-violating effect resulted from the interference between the Cabibbo-favored and the doubly Cabibbo-suppressed amplitudes with the neutral kaon mixing. Future measurements of branching fractions play a critical role in reducing the uncertainties.