Theoretical Study of Electron Capture, Excitation, and Ionization Processes in H+−H(2l) Collisions

Abstract

The processes of single-electron charge exchange, excitation, and ionization during proton impact on H(2 l ) are investigated. We employ two different theoretical methods that are suitable for different collision energy regions: the full quantum-mechanical molecular orbital close-coupling method for energies from 0.001 to 1 keV u ^−1 and the two-center atomic orbital close-coupling (TC-AOCC) method for energies between 0.3 and 100 keV u ^−1 . For charge exchange and excitation processes, the total and nl -resolved cross sections to the final reaction channels of H ( nl , n = 1–4) have been obtained over a broad energy region. Moreover, the ionization cross sections in the TC-AOCC calculation are also reported for both H(2 s ) and H(2 p ) initial target states. The present results are all compared with those from other sources when available. It is found that the magnitude and energy behavior of nl -resolved excitation cross sections for H ^+ –H(2 p ) collisions are significantly distinct from those of the H(2 s ) initial state in the entire energy range considered, particularly in the low-energy region. The energy behaviors of the nl -resolved charge exchange cross sections from the H(2 p ) initial state are similar to those from the H(2 s ) initial state, but their magnitudes are larger. The present accurate cross-section data are anticipated to provide insight into the research of astrophysics and controlled fusion plasmas.

Keywords

• Ionization
• Laboratory astrophysics
• Collision processes