Memory effects in speed-changing collisions and their consequences for spectral lineshape: I. Collision regime

Abstract

A consistent approach to the lineshape in the binary collision regime accounting for speed-changing collisions based on a convenient memory function is proposed. The consequences of memory effects on the spectral lineshape, through speed-dependent line broadening and line shifting mechanisms, are studied in detail for the prototype H2-Ar system. The connection between the present memory approach and the analytical model SC + D (“speed changing” and “dephasing” collisions) based on the hard collision approximation is displayed.