Chiral bands, dynamical spontaneous symmetry breaking, and the selection rule for electromagnetic transitions in the chiral geometry

A model for a special configuration in triaxial odd-odd nuclei, which exhibits degenerate chiral bands, dynamical symmetry breaking, and the selection rule for electromagnetic transitions in the chiral geometry, was investigated. A quantum number obtained from the invariance of the model Hamiltonian, was determined. The selection rules for electromagnetic transition probabilities in chiral bands was also derived in terms of this quantum number. The degeneracy of lowest two bands was obtained in numerical diagonalization of the Hamiltonain at an intermediate spin range.