Higher-rank discrete symmetries in the IBM. II Octahedral shapes: Dynamical symmetries

A. Bouldjedri , S. Zerguine , P. van Isacker (1)

1 GANIL - Grand Accélérateur National d'Ions Lourds

The symmetries of the sdg -IBM, the interacting boson model with s , d and g bosons, are studied as regards the occurrence of shapes with octahedral symmetry. It is shown that no sdg -IBM Hamiltonian with a dynamical symmetry displays in its classical limit an isolated minimum with octahedral shape. However, a degenerate minimum that includes a shape with octahedral symmetry can be obtained from a Hamiltonian that is transitional between two limits, Ug(9)⊗Ud(5) and SOsg(10)⊗Ud(5) , and the conditions for its existence are derived. An isolated minimum with octahedral shape, either an octahedron or a cube, may arise through a modification of two-body interactions between the g bosons. Comments on the observational consequences of this construction are made.

Mots clés: Discrete octahedral symmetry; Interacting boson model; g bosons

Domaines: Physique Nucléaire Théorique [nucl-th]

A. Bouldjedri, S. Zerguine, P. van Isacker. Higher-rank discrete symmetries in the IBM. II Octahedral shapes: Dynamical symmetries. Nucl.Phys.A, 2020, 1003, pp.122028. ⟨10.1016/j.nuclphysa.2020.122028⟩. ⟨hal-02953265⟩