Hyperon production in Lambda(+)(c) -> K(-)p pi(+) and Lambda(+)(c) -> K(S)(0)p pi(0)

Abstract

We investigate S = -1 hyperon production from the Lambda(+)(c) -> K(-)p pi(+) and Lambda(+)(c) -> K(S)(0)p pi(0) decays within the effective Lagrangian approach. We consider the Sigma/Lambda ground states, Lambda(1520), Lambda(1670) (J(p) = 1/2(-)), Lambda(1890)(J(p) = 3/2(+)); Lambda/Sigma-pole contributions from the combined resonances between 1800 and 2100 MeV; and N/Delta-pole and K*-pole contributions, which include the proton, Delta(1232), and K(892). We calculate the Dalitz plot density (d(2)Gamma/dM(K-p)dM(K-pi+)) for the Lambda(+)(c) -> K- p pi(+) decay. The calculated result is in good agreement with experimental data from the Belle collaboration. Using the parameters from the fit, we present the Dalitz plot density for the Lambda(+)(c) -> K(S)(0)p pi(0) decay. In our calculation, a sharp peaklike structure near 1665 MeVis predicted in the Lambda(+)(c) -> K(-)p pi(+) decay because of the interference effects between the.o1670thorn resonance and eta-Lambda loop channels. We also demonstrate that we can access direct information regarding the weak couplings of Lambda(1670) and Sigma(1670) from the Lambda(+)(c) -> K(S)(0)p pi(0) decay. Finally, a possible interpretation for the 1665 MeV structure beyond our prediction is briefly discussed.