- th / 0 50 50 18 v 1 6 M ay 2 00 5 Shape Phase Transition of the States Between the U ( 5 ) and SU ( 3 ) Symmetries and with Certain Angular Momentum

- th / 0 50 50 18 v 2 8 J ul 2 00 5 Shape Phase Evolution of the Axially Symmetric States Between the U ( 5 ) and SU ( 3 ) Symmetries

The shape phase structure and its transition of the nucleus in the transitional region between the U(5) and SU(3) symmetries is restudied in the framework of coherent-state theory with angular momentum projection in IBM-1. The certain angular momentum (or rotation-driven ) effect on the nuclear shape is discussed. A coexistence of prolate and oblate shapes is found for the ground states of the ...

What can we learn from the Interacting Boson Model in the limit of large boson numbers ?

Over the years, studies of collective properties of medium and heavy mass nuclei in the framework of the Interacting Boson Approximation (IBA) model have focused on finite boson numbers, corresponding to valence nucleon pairs in specific nuclei. Attention to large boson numbers has been motivated by the study of shape/phase transitions from one limiting symmetry of IBA to another, which become ...

ar X iv : n uc l - th / 0 50 30 71 v 1 2 9 M ar 2 00 5 Quantum Phase Transitions in the U ( 5 ) − O ( 6 ) Large N limit

The U(5) − O(6) transitional behavior of the Interacting Boson Model in the large N limit is revisited. Some low-lying energy levels, overlaps of the ground state wavefunctions, B(E2) transition rate for the decay of the first excited energy level to the ground state, and the order parameters are calculated for different total numbers of bosons. The results show that critical behaviors of these...

ar X iv : n uc l - th / 0 50 50 24 v 1 9 M ay 2 00 5 Structure of isomeric states in 66 As and 67 As

l - th / 0 50 90 03 v 1 1 S ep 2 00 5 X ( 5 ) Critical - Point Structure in a Finite System

X(5) is a paradigm for the structure at the critical point of a particular first-order phase transition for which the intrinsic energy surface has two degenerate minima separated by a low barrier. For a finite system, we show that the dynamics at such a critical point can be described by an effective deformation determined by minimizing the energy surface after projection onto angular momentum ...