Pair-truncated shell-model approach to backbending and low-lying states in 132Ba -: art. no. 044305

Backbending phenomena and low-lying collective states in the nucleus Ba-132 are studied in terms of a pair-truncated shell model with the monopole and quadrupole pairing plus quadrupole-quadrupole interaction. The model reproduces well experimental energy levels, transition rates, and g factors for both low-lying states and those around the backbending region. The collective pair truncation of the shell-model space yields remarkable results for low-lying states, and the alignment of two 0h(11/2) neutrons plays a decisive role in describing the backbending.