Small angle scattering of hydrogen from surfaces

Abstract

Scattering of H + or H − and H 0 as a result of H +, and D + impact has been studied for targets of Be, C, Cu, Nb, Au, and stainless steel. Projectiles are incident at 69° from the surface normal and scattered particles are studied at near grazing emergence angles. Charge state distribution of the scattered particles is a function only of recoil energy and not impact energy nor of emergence direction. This indicates that the charge states are governed by bi-particle collision events rather than interactions with band structure of the surface. Comparison with previous experiments shows that as the incidence angle increases the average recoil energy gets larger. As an indication of absolute magnitudes we find that for 15 keV H + incident on Au at 69° from the surface normal, there are 0.081 protons, and 0.0072 H −, and 0.263 neutral hydrogen atoms scattered per incident proton and per steradian at an angle of 9.4° from the surface.