DESCRIPTION OF ENERGY LEVELS AND DECAY PROPERTIES IN ¹⁵⁸Gd NUCLEUS

In this paper, IBM-1 and IBM-2 with a SU(3) limit are used to describe the Gd-158 isotope. The calculations of energy levels in the ground state, beta-, and gamma-bands are made up, which account for 15 energy levels. However, we found that the energy states of the same spin of the beta- and vibrational bands become degenerate states. In breaking the SU(3) dynamical symmetry by introducing a value of pairing interaction, the degeneracy is lifted and the energy levels are brought up to the same order as the experimental ones.