<i>G</i>-Matrix Approach to Hyperon-Nucleus Systems

Abstract

The properties of the new {itYN} · {itYY} interaction model ESC08 are studied on the basis of the {itG}-matrix theory. G-matrix calculations in nuclear matter are performed in the cases of Λ{itN}-, Σ{itN}-, Ξ{itN}- and ΛΛ-starting channels. In the Λ{itN} case, the spin-spin and spin-orbit terms are shown to be of reasonable strengths. The folding-model analyses are done extensively for observed spectra of Λ hypernuclei. The experimental energy spectra are nicely reproduced. The shell-model analyses for typical Λ hypernuclei are performed with the {itG}-matrix interactions. In the Σ{itN} case, the repulsive values of {itU}{inΣ} are obtained owing to the effect of the quark Pauli-forbidden states which are taken into account phenomenologically in ESC08. In the Ξ{itN} case, the moderately attractive values of {itU}{inΞ} are obtained mainly due to the strongly attractive contributions in {su3}{itS}{in1}{itT} = 1 Ξ{itN}-ΛΣ-ΣΣ coupled states, which leads to extensive existence of Ξ hypernuclei. In the ΛΛ case, the {itB}{inΛΛ} values derived from ESC08 are found to be consistent with the experimental values.