Two nucleon induced hypernuclear weak decay within a nuclear matter formalism

摘要

The non-mesonic two-nucleon induced hypernuclear decay is studied using a non-relativistic nuclear matter formalism, which is supplemented with the local density approximation (LDA) to evaluate the C-12(Lambda) decay width. Three possible decay mechanisms: Gamma(Lambdann --> nnn), Gamma(Lambdanp --> nnp) and Gamma(Lambdapp --> npp), are considered. The full one-meson-exchange model (OMEM), which includes the complete pseudo-scalar and vector meson octets (pi, eta, K, rho, omega, K*), is employed for the transition potential. The strong residual interaction, which accounts for the ground state correlations, is modeled by a Bonn potential. Our results show that the two-nucleon induced decay is similar to24% of the total non-mesonic decay width. We also confirm that this decay is dominated by the process Lambdanp --> nnp, even though the two other decay channels should not be neglected. (C) 2004 Elsevier B.V. All rights reserved.