Systematic Analysis Of Nuclear Rotational Spectra By Using Two-parameter Formulas

This thesis can be divided into two parts, the summary is as follows:Part I: In recent years, the experimental data of rare-earth region and actinide regionof even-even nuclei have made new discoveries, these experimental data include:energy and moment of inertia, the progress of the experiment brought a lot of promotionto the theory, these experimental data have a wide range of applications, such an thefield of medical technology, military applications, and statistical models.The main content of this part is proceeding from the commonly used two-parameterformulas, we make a dissemination of these half-phenomenological formulas and makereasonable adjustments to the parameters. The purpose is make it more accurately todescribe the variation of a series of parameters. Firstly, we analysis the rare-earth andactinide region of even-even nuclei basebands by using these formulas, followed by abrief analysis of vibrational bands of γ and β, we also analyzed the superdeformedbands of A=130and A=190, and then we compared the experimental results withthe theory, we found that not only the ab formula can give a good results but also pqformula can give a very good fitting of experimental data, even for some of the band willgive better results. Meanwhile, this part also gives the curve between the moment ofinertia and the energy. These results also proved once again that when the spin becomelarger, the pq formula can also give good agreement with the experiment. Finally, weuse these two formulas to analyze the spectrum of¹⁷⁰Yb, the analysis shows that inaddition to the basebands, the vibrational bands of the Gamma and Beta, ab formula,and pq formula can give better fitting results in the calculation of the other bands.Part II: We all know that so many authors made the studies about nuclear structure,they has put forward a variety of theoretical models, such as the Fermi gas model, theliquid drop model, shell model, collective motion model and interacting boson model（IBM model）.Since Bohr and Mottelson proposed the coupling between particle（quasiparticle） with a different vibration （for example, quadrupole vibration and 0vtupole vibration）, many authors developed this model in their calculations. When themass number A is in the middle or more bigger, many authors have considered thiseffect in their studies, and this effect can be a good explanation of the energy spectrum.Therefore, this is a meaningful work to apply this coupling effect in the lighter nuclei.That part proceeding from the article of [1], in1970they gave analysis about³³S and³⁴S. Now, more and more experimental values about the energy spectrum arediscovered, so we re-do the calculation of³³S by using these experimental data, wefind that our theoretical spectra and experimental spectra match well. In addition, wefurther indicates that the applicability of the intermediate coupling model.