Structure of the ground and excited states in ${}_{\Lambda }^9$Be nucleus

Abstract

We investigate properties of bound and resonance states in the ${}_{\Lambda }^9$Be nucleus. To reveal the nature of these states, we use a three-cluster $2\alpha +\Lambda$ microscopic model. The model incorporates Gaussian and oscillator basis functions and reduces a three-cluster Schrödinger equation to a two-body like many-channel problem with the two-cluster subsystems (${}_{\Lambda }^5$He and ${}^8$Be) being in a bound or a pseudo-bound state. Influence of the cluster polarization on the energy and widths of resonance states in ${}_{\Lambda }^9$Be and on elastic and inelastic ${}_{\Lambda }^5$He+$\alpha$ scattering is analyzed.

Comments: 42 pages, 5 figures, extended version of the paper, submitted to Nucl. Phys. A