Coupled-channels Optical Studies For Electron-nitrogen Ionization And Positron-hydrogen Resonances

The investigation of the electron-atom collision processes plays an essential role in the studying of the interaction of electron with general matter can afford some information of motion and correlation which the interaction of general matter with general matter can not afford. Data on electron impact ionization of atomic nitrogen are obviously of interest for both physical science and industrial applications. However, because of the experimental difficulties and the limitation of the theoretical method, the quantitative knowledge of electron-impact ionization cross sections of N atom is very insufficient for these applications. Nitrogen atom has open-shell structures, so its electron correlation and channel coupling are more marked. There is an acute need for more theoretical methods to investigation the problems in the processes of the electron-atom collision. Since the complex of the processes, the available experimental ionization cross-section data of electron impact on nitrogen are rather scarce.The atomic system that consists of a positron and a hydrogen atom has attracted considerable interest. Especially, we should not take into account the exchange symmetry. Some scientists take most interest in the positron hydrogen impact resonances. In recent years, several methods have been used to calculate resonances in e+-H scattering. Such as hyperspherical function method, close-coupling method, R-matrix method, complex-coordinate rotations method. But some of these methods have their limitation. Until recently, the resonances in e+-H scattering have yet to be observed in laboratories.In this paper, we first used the ab inito continuum equivalent-local potential method to study the ionization cross section of the electron impact on the open-shell nitrogen atom. And the present calculation were compared with the experimental data and other theoretical calculation results. The comparison show that the ab inito continuum equivalent-local potential method is capable to calculate electron scattering from open-shell atoms, despite we use a quite simple model to represent the wave functions of the target. Furthermore, there is an intense need for experimental and possibly additional theoretical studies in order to establish reliable electron scattering data for atomic carbon.We have also calculated the resonances in e~+-H scattering using the momentum space coupled channels optical (CCO) method and compared our calculation with the complex-coordinate rotations method results. The comparison show that the present method can commendably obtain the shape and the position of the e~+-H resonances.