Electromagnetic Properties in Samarium Isotopes Within the Framework of the IBM-2

Abstract

Electromagnetic transitions between low-lying states in deformed even-even 148–154Sm nuclei were investigated within the framework of the SU(3) limit of the neutron-proton interacting boson model. To explain the M1 transitions between low-lying states and the E2 transition between interband states, we applied first-order perturbation theory by adding the proton-neutron quadrupole interaction Qπ· Qv that breaks F-spin symmetry in the dynamical symmetric SU(3) Hamiltonian as a perturbed term. We calculated the transition probabilities of the M1 and the E2 transition operators between low-lying interband states by using the 1/N expansion methods. The matrix elements of the proton-neutron quadrupole interaction Qπ· Qv were directly calculated, as shown in a previous study, by applying the F-spin operator Qπ· Qa instead of Qπ· Qv. The results of the present study for electromagnetic transitions were applied to some deformed even-even Samarium nuclei, and these theoretical results could effectively describe the experimental data.