Semiclassical close coupling calculation of the electron capture cross section for N^{4+} + H collisions

• Main Authors: Hurng-Chun Lee, 李宏春
• Other Authors: Hsiang-Chi Tseng
• Format: Others
• Language: en_US
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/83124831432614584633

碩士 === 中原大學 === 物理學系 === 87 === Due to the possible applications in astrophysics and plasma physics in recent years, ion-atom scattering problem has become one of the most interesting topics in atomic physics. For electron capture processes in N^{4+}-H scattering, there are only few up-to-date molecular orbital (MO) calculations and various structures of total cross sections are predicted by different theoretical calculations in low energy regime. To investigate the origin of discrepancies among the MO results, we make a careful calculation for total and partial cross sections of this scattering system with collision energies from 30 eV/amu to 3500 eV/amu by using a so-called "two center atomic orbital (TCAO) semiclassical close-coupling model". In view that two electron processes such as double capture and simultaneous projectile-core excitations are small, we employ the one-electron model in this calculation. The effective potential performed by inner core is modified by diatomic model potential which can predict the N^{3+} and H atomic bound energies precisely on individual atomic center. Two AO basis sets have been used to check the convergence of the calculation and the results show that the pseudo-orbitals are not important in the calculation. On the other hand, we also use a heuristic coulomb trajectory correction to account for the trajectory effect in low energy regime. By including the trajectory correction, our results are generally in agreement with the theoretical calculation by Shimakura et. al. [12] in 1992 and experimental data by Folkerts et. al. [4] in 1995. However, we do not reproduce the structures predicted by various MO results in low energy regime.