Velocity selective rotational rainbows for normal incidence/normal detection gas–surface scattering

Abstract
Velocity selected rotational state distributions of N2 molecules scattered from Ag(111) have been measured. These measurements have been made at normal incidence and normal detection for incident energies of 0.25 and 0.75 eV. This new technique allows us to rapidly study the cross correlation between the exit rotational state and its velocity distribution. A pronounced difference between the rotational distributions of fast and slow scattered molecules is observed, and this difference is much more pronounced for high incident kinetic energy.