The Interacting Boson-fermion Model Description For Transitional Odd-A Nuclei

The interaction boson-fermion model is one of the successful nuclear models in description of low-lying properties of odd-A nuclei.Up till now,there have been many works using the interaction boson-fermion model to describe odd-A nuclei in the transitional region,but a unified model description of both even-even and odd-A nuclei simultaneously with detailed analysis is still necessary.Moreover,very recently,a new particle-rotor model in description of the transitional odd-A nuclei has been proposed by our group.Therefore,it is practically necessary to carry out a unified model calculation for both even-even and odd-A nuclei and in comparison with the experimental data and the results of the new particle-rotor model.In this thesis,a consistent description of both even-even and odd-A nuclei in the transitional region with detailed analysis is made in the interaction boson-fermion model framework.Matrix elements of the operators under the(U(6)?O(6)?SO(5)?SO(3))(?)(U(2j+1)?SU(2))?SU_J(2)basis of the model are derived,for which a computation code is complied accordingly.As an initial application,the model is applied to describe the low-lying level energies,some B(E2)values,and electric quadrupole moments of low-lying states of ^134,135Ba and ^130,131Xe.The results are compared to the experimental data and those of other models,especially those of the new particle-rotor model.It is shown that the low-lying properties of these nuclei are basically reflected by the fitting results,which,in turn,shows the applicability of the model to the transitional region.In addition,the fitting results of the new particle-rotor model to the level energies,reduced E2 transition rates,and ground-state electric quadrupole moment are better in relatively lower energy region,which indicates the applicability of the new particle-rotor model.