ABSTRACT
In deformed shell model, i.e., DSM , just as in the standard spherical shell model (i.e., SM), for a given nucleus one first assumes that there is an inert core of nucleons and starts with valance nucleons in a model space consisting of an appropriate set of sp orbitals and two-body effective interaction matrix elements. By solving the HF sp equation self-consistently (discussed ahead), the lowest energy prolate and oblate deformed intrinsic states are obtained along with deformed sp states for protons and neutrons. Figures 2.1 and 2.2 show examples. Then, various excited intrinsic states are generated by making particle-hole excitations over the lowest intrinsic states from prolate and oblate solutions (see Figures 2.1 and 2.2). These intrinsic states do not have definite angular momentum and are superposition of several states of good angular momentum. States of good angular momentum are projected from each of these intrinsic states. Since these projected good angular momentum states will not be orthogonal to each other, they are first orthogonalized. Then the Hamiltonian matrix is constructed in the basis of these orthonormalized states and diagonalized. Using the resulting wavefunctions, all the needed observables are calculated. It should be emphasized that in DSM, the HF approach in a limited configuration space is used to generate a deformed shell model basis, where mixing a few low lying configurations is sufficient to give most of the important features and systematics of spectroscopic properties. Thus, DSM may be viewed as an approximation to full shell model.
