Abstract
By introducing into the single-collision model a flux-attenuation factor both in the incoming flux and in the outgoing flux, together with a reduced particle energy, we have derived more comprehensive analytical expressions for the number and energy reflection coefficients for all incident-target-atom combinations, leading to a simple explicit representation of the reflection flux under certain approximations. This gives the general qualitative tendency of the light-particle reflection, while a more quantative knowledge should be obtained from computer simulations or analytical approaches including numerical calculation for multiple collisions.