Critical point symmetry for the spherical to triaxially deformed shape phase transition

The critical point T(5) symmetry for the spherical to triaxially deformed shape phase transition is introduced from the Bohr Hamiltonian by approximately separating variables at a given γ   deformation with 0°≤γ≤30°0°≤γ≤30°. The resulting spectral and E  2 properties have been investigated in detail. The results indicate that the original X(5) and Z(5) critical point symmetries can be naturally realized within the T(5) model in the γ=0°γ=0° and γ=30°γ=30° limit, respectively, which thus provides a dynamical connection between the two symmetries. Comparison of the theoretical calculations for 148Ce, 160Yb, 192Pt and 194Pt with the corresponding experimental data is also made, which indicates that, to some extent, possible asymmetric deformation may be involved in these transitional nuclei.