Microscopic look at backbending
Abstract
A shell-model calculation of high-spin phenomena in the highly neutron deficient Ba-Ce-Nd region is reported. An inert spherically symmetric Z=50=N core is assumed with extracore nucleons distributed among the g72, d52, d32, s12 normal-parity orbitals and the unique parity h112 orbital with the number of particles within each set fixed. The normal-parity subspace is further truncated to a single irreducible representation of pseudo SU(3) made effective through the mapping (g72d52d32s12)→(f72f52p32p12). A five-dimensional quasispin classification is used for the unique-parity h112 space which is restricted to states with seniority zero and two. Using a surface delta interaction we are able to reproduce the observed backbending in Ba7056126. The model affords a microscopic look at Coriolis antipairing and pair realignment phenomena. NUCLEAR STRUCTURE Ba56126; Shell-model interpretation of backbending, pair realignment, and Coriolis antipairing; h112; g72d52d32s12 configurations with pseudo-SU3 truncation. © 1979 The American Physical Society.