Relativistic Theoretical Study On Fine Structures And Processes Of Photoionization And Radiative Recombination Of Highly Charged Ions

The content of atomic structure, atomic spectra and various of collisions is one of the most important branches in the field of atomic physics, and has a wealth of practical application in many aspects such as interpreting and foreseeing the scheme of X-ray laser, analyzing the thermodynamic equilibrium in plasma and performing the experiment of controlled nuclear fusion and so on. In this dissertation, a systematical study on the fine structure, photoionizationa, radiative recombination and their related processes of highly charged ions has been carried out.An introduction has been given in Chapter one, which showed some main background of this work; Chapter two described the multiconfigration Dirac-Fock (MCDF) method, and formula of radiative transition probability, photoionization cross section, radiative recombination cross section and the corresponding atomic data carefully; In Chapter three, energy structures and forbidden (M1, M2, E2) transition probabilities between the ground state 3s²3p⁶3d^{10 1}S₀ and the low-lying excited 3s²3p⁶3d⁹4l, 3s²3p⁵3d¹⁰4l and 3s²3p⁶3d¹⁰ 4l (l=s,p, d,f) states have been calculated for Ni-like ions of Z=45-95, by using GRASP92 package and REOS99 code based on the relativistic multiconfiguration Dirac-Fock method. By Analyzing the effects of strongly configuration interaction (CI) existing in Ni-like sequence, the abnormalities of forbidden transition probabilities existing in several highly charged Ni-like ions were explained, some general laws for the influence of CI on forbidden transition probabilities were discussed; In Chapter four, ionization energies and the corresponding photoionization cross sections from the 1s, 2s, 2p and 3s subshells of Fe¹⁵⁺ ion have been calculated systematically using a newly developed program RERR06 for the first time, which was based on the widely used GRASP92 and RATIP packages. In the calculation, the effects of configuration interaction and orbital relaxation have been considered. As a result, the shake-up processes accompanied by the main photoionization processes have been treated as unified. And then, photoexcitation autoionization of its 2p ions has also been studied. In Chapter five, radiative recombination cross sections of U⁹¹⁺ ions have been calculated by the RERR06, and radiative decay of U⁹⁰⁺ ions generated in the radiative recombination of U⁹¹⁺ ions have also been studied; In Chapter six, radiative electron capture (REC) for the collision of 98MeV/u U⁸⁹⁺ ions with N₂ target molecules has been mainly studied, in the light of impulse approximation, the x-ray spectra for REC in the collision of U⁸⁹⁺ ions with N₂ can be obtained by convolving the radiative recombination cross section (RRCS) and the N₂ Compton profile (CP) which was modeled by virtue of the polynomial form. There has been a very good agreement between the calculated and experimental spectra, as the contribution of each line for raditive recombination to the total spectra can also be identified. In addition, a detailed method has also been attempted to simulate the radiative deexcitation cascade (RDC) spectra following the REC processes, although the theoretical spectra are shifted and much smaller than the experiment, some interesting results have been obtained; in the seventh chapter, some summarization and a vista of the future work have been given.