Single- and Double-Electron Capture Processes in Low-Energy Collisions of N^4+ Ions with He

We investigate the electron capture processes of N^4+(1s^22s) colliding with He(1s^2) in the energy range of 10–1700 eV/amu using the quantum-mechanical molecular-orbital close-coupling (QMOCC) method. Total and state-selective single-electron capture and double-electron capture (SEC and DEC) cross sections are obtained and compared with other available studies. The results agree better with the experimental data in both trend and magnitude when the electron translation factor (ETF) effects are included. Our results indicate that both the SEC and DEC processes play important roles in the considered energy region. For the SEC processes, the N^3+(1s^22p^2) + He^+(1s) states are the dominant capture states, and the N^2+(1s^22s2p^2) + He^2+ states are the main DEC states.