Effect of Expansion of the Core to the Nuclear Radius in Oxygen Isotopes

Abstract

We study nuclear sizes and a mechanism of the sudden change of the radius at 23 O by using the cluster-orbital shell model approach. The overall agreement of the calculated radii to those obtained by the experiments is good. The key mechanism is that two different configurations contribute the nuclear size, and the Pauli-blocking effect makes a selection of a particular configuration of the core. As a consequence, the sudden change at 23 O is qualitatively reproduced.