Nuclear supersymmetry and quantum shape-phase transition

In this paper, the characteristics of nuclear supersymmetry in transitional nuclei are investigated. The structure of the two types of nuclear supersymmetry schemes, based on the U(6/2) and U(6/4) supergroups, is discussed. We focus on the quantal analysis and present the phase transition observables such as the level crossing, the expectation values of the d-boson and the fermion number operators. It is found that the relation between the even–even and odd-A neighbors implied by nuclear supersymmetry in addition to dynamical symmetry limits can be also used for transitional regions. Experimental evidence for the occurrence of vibrational to gamma-unstable transition in Ru–Rh and Zn–Cu supermultiplets is presented. We show that the second-order nature of the phase transition from U(5) to O(6) may exist in Ru–Rh and Zn–Cu supermultiplets.