Study some of the nuclear characters of Samarium 148,150,152,154Sm isotopes in the IBM-1 framework

Abstract

The interacting boson model IBM-1 has been applied to some 62Sm even-even isotopes .
This study has included calculation of the positive-parity collectiv g-band and β,γ –degenerate bands of 148 62Sm, 150 62Sm, 152 62Sm and 154 62Sm isotopes and compared with experimental values of energy level. The used Hamiltonian parameters correspond to description close to the U(5)-SU(3). The potential energy surfaces E(β,γ) as function of geometrical parameter β and γ for these isotopes can be obtained where they were represented by contour lines and the minimum value of deformation factor βmin was fixed , which was in front of Emin, and so the γ factor. The transition from the spherical to the rotational shape can be observed in these isotopes. In the framework of IBM-1 , what we conclude from the energy spectra study and the geometrical picture of potential energy surface for these nuclei is that these nuclei are spherical shape (U(5)symmetry), prolate rotational shape (SU(3)symmetry) and deformed shape between these two symmetry limits in the U(5)-SU(3)transitional region .