DEFORMED NUCLEI AND MOMENTS OF INERTIA

Abstract

The earliest nuclear models were developed to the a- decay and the reactions of the nucleons with nuclei. The reaction mod­ els made the extreme assumptions of the weak interaction cor­ responding to independent particle motion, the potential model of Bethe [1], and the strong interactions made the compound nucleus model of Bohr [2]. The subsequent more highly developed nuclear models can be divided into semiclassical and quantum mechanical models, and then into the independent particle model and the collective model. The simplest collective model in which the nucleus is consid­ ered to consist of a core and extra core particles, with the core being treated as a liquid is known as the liquid drop model [1]. The real problem of A interacting particles has, in general, no exact solutions. There are, however, cases in which the inter­ action of one particle with all others can be replaced, to a good approximation, by an average central field. It is then possible to treat the problem by solving, for each particle, the one-particle problem in a central field.The description of a system of interact­ ing particles in terms of independent particles moving in a cen­ tral field is called a shell model [3]. The nuclear shape which is characterized by this potential was spherically symmetric. This is true for nuclei with closed or nearly closed shells. Nuclei in which the last shell is approximately half-filled are characterized by considerable deformations.