Simultaneous study of the 11Li and 10Li nuclei in a microscopic cluster model

The 11Li and 10Li nuclei are investigated in the generator coordinate method involving 9Li+n+n and 9Li+n cluster configurations, respectively. The 9Li nucleus is described in the shell model with all p-shell wave functions allowed by the Pauli principle. This procedure yields many 9Li states, defined by a flexible mixing of shell model basis states. Two different nucleon-nucleon interactions are used. We compute some spectroscopic properties of 11Li, such as radii, quadrupole moments and densities. The model predicts a 1/2- excited state, but no positive-parity state. With the same conditions of calculation, we study the 10Li system. We find a 1+ assignment for the ground state. We present the s phase shifts, and discuss the possible existence of a low-energy virtual s state. The properties of such a state are shown to be partly model dependent. (orig.)