Excited Enhanced Transition Form¹⁷⁸Hf Isomer And Study Of Deformed Nuclei

At this thesis, we firstly introduced the development history of nuclear structure, researchcontents and current situation, theories of nuclear structure model and deformed nucleardescription methods. Subsequently, this paper briefly introduces a model, namely the crankedshell model and the calculations of potential energy surface based on it, the TRS method, anddiscussed its advantages and disadvantages, and then we introduced the projected shell modeltheoretical framework. We applied these models to make the job of the following respects:(1) We used the Woods-Saxon shell model to study the possible triaxial deformations ofnuclear states, including deformation excited state. In order to find a nuclear state may havingtriaxial deformations, Total-Routhian-Surface calculations by means of thepairing-deformation-frequency self-consistent cranked shell model have been carried out forgermanium and selenium isotopes. In74Ge we found in the ground state and the collective state atriaxial deformation with γ=30°, which is the largest of triaxial deformations. In our TRScalculations, Ge and Se isotopic shape shows aγ soft triaxial deformations, especially74Geshowed the most significant triaxial deformations.(2)178Hf long-lived isomer excitedγ transition potential gateway states or calledintermediate trigger states are discussed in the framework of projected shell model andconfiguration-constrained (diabatic-blocking) method, we obtained the178Hf energy of2.446MeV 16+of isomor energy states and near the levels structure data, and excited to these intermediatestates and subsequently the deexcitation of transition probability. Calculated three levels isrelatively close to the long-lived isomer state, their configurations and long-lived isomerconfiguration are really close, there should be a strong transition probability, We hope thistheoretical will provide for isomer excited transition study a theoretical support.