Spin dependence of theΛN effective interaction

Abstract

A combination of theoretical estimates, based on a ΛN potential model and phenomenological analysis of hypernuclear data, is used to determine a set of four $p_{\mathrm{N}{s}_{\Lambda }}$ two-body matrix elements which characterize the spin dependence of the ΛN interaction in the p shell. The central spin-spin and the Λ spin-orbit matrix elements are most strongly constrained by existing data. The spin dependence is weak in the sense that (core)×$s_{\Lambda }$ doublet splittings are predicted to be of order 100 keV, except for the special case of ${}_{\mathrm{\Lambda }}{}^7{}_{}{}^{}\mathrm{Li}$ where the central spin-spin interaction dominates and the ground state doublet splitting is likely to be of order 600 keV. Detailed consideration is given to those γ ray transitions the observation of which would best serve to further constrain the spin dependence of the ΛN interaction, particularly the tensor interaction.