Theoretical Study Of Opacity In Plasmas

The radiative properties of hot dense plasmas play an important role in ICF researches. The relevant atomic data for X-ray emission and absorption processes are necessary physical parameters in theoretical simulations and in analysis of diagnostic measurements for ICF plasmas. It is usually necessary to consider thousands of ionic energy states and transition arrays between these energy states.The average atom model(AA) is adopted for practical purpose .However, the average atom and relevant parameters( the average orbital energies, the average rate coefficients etc.) are only suitable for the most abundant ions and will be unsuitable for the other ions in the plasmas. People have made some attempt beyond the AA model by modifying the binomial formula, but the AA orbital energies and ion configuration model's orbital energies are approximately calculated by More's screening hydrogenic atomic structure model.but it is demanded to self-consistently calculate the AA orbital energies and detailed configurations' energies seperately to meet the requirement of the precision physics.In Section 3, we systemly propose a method beyond the AA model, which can calculate the ionic populations of plasma in local thermal equilibrium(LTE) with satisfactory accuracy, and may also deal effectively with the ionic populations of plasma in non-local thermal equilibrium(n-LTE).To calcuate the ionic populations in n-LTE plasmas, the detailed configurations' rate coefficients are needed, which are acquired by the appropriate corrections from AA reduced rate coefficients. In Section 4, the inherent rules between the reduced photonionization cross-sections of Br are carefully analyzed. Then, we propose a method to get the detailed configurations' rate coefficients of photonionization and radiative recombination via AA reduced photonionization cross-sections. This work is the necessary preparation for accurate description of n-LTE plasma.