On the Collective Mode of Internal Motion of the Nucleus to be coupled with the Irrotational Surface Motion

Abstract

From the analyses of unsatisfactory points in the usual irrotational collective model, it has been considered that there should exist a kind of “internal” rotational collective motion to be coupled with the usual irrotational sufrace motion. Using Watanabe's method, a generalization of the collective description with redundant variables is developed and it is shown that the introduction of the rotational collective motion is indispensable in describing the collective motion in a closed form consistently. It is confirmed that this rotational mode plays an important role in explaining the discrepancy between the experimental and theoretical values of the effective moments of inertia of nuclei. The fundamental assumption of the various models concerning the moments of inertia is discussed.