Inelastic Transition Probabilities and Their Role in the Quenching of Glory Extrema in Atom–Diatomic Scattering

Abstract

Rotational inelastic transitions in atom–diatomic collisions have been investigated via several approximation treatments. In the high‐velocity limit the restricted distorted‐wave approximation (RDWA) yields transition probabilities $\mathrm{P)j\hspace{0.17em}\to \hspace{0.17em}j\prime )}$ , in agreement with the first‐order sudden approximation at all impact parameters. Calculations of $\mathrm{P(j\hspace{0.17em}\to \hspace{0.17em}j\prime )}$ at the glory impact parameter by the RDWA (further reduced by incorporating the Born approximation) agreed well with computations by the full distorted‐wave procedure (over a wide range of energies and anisotropy parameters). In the pure distorted‐wave treatment no glory quenching arises due to inelastic effects; however, in higher‐order approximations inelastic quenching becomes important. By the use of a renormalized distorted‐wave procedure (designed to preserve the unitarity of the S matrix) an improved equation for $\mathrm{P(j\hspace{0.17em}\to \hspace{0.17em}j\prime )}$ is developed, leading to a quenching formula equivalent to that of Cross (based upon the high‐velocity limit of his “infinite‐order” distorted‐wave treatment).