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

Electromagnetic transitions between low-lying states in deformed even-even 148–154 Sm nuclei were investigated within the framework of the SU(3) limit of the neutron-proton interacting boson model. To explain the M 1 transitions between low-lying states and the E 2 transition between interband states, we applied first-order perturbation theory by adding the proton-neutron quadrupole interaction Q π · Q v that breaks F -spin symmetry in the dynamical symmetric SU(3) Hamiltonian as a perturbed term. We calculated the transition probabilities of the M 1 and the E 2 transition operators between low-lying interband states by using the 1/ N expansion methods. The matrix elements of the proton-neutron quadrupole interaction Q π · Q v were directly calculated, as shown in a previous study, by applying the F -spin operator Q π · Q a instead of Q π · Q v . 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.