Resonances and alignment effects in Na-Ar fine-structure-changing half collisions

In this paper we present a calculation of intensities and polarization of the fluorescence from the Na two $^{2}$${\mathit{P}}_{3/2}$ and $^{2}$${\mathit{P}}_{1/2}$ states, at \ensuremath{\lambda}=589.16 and 589.76 nm, respectively, produced by photodissociation of the Na-Ar van der Waals molecule. We have used a coupled-channel wave-packet method that includes all the relevant interactions and coherence between the collision channels [J. Chem. Phys. 95, 8124 (1991)]. We show that it is possible to obtain distinct insights into the dynamics of fine-structure-changing processes via such half-collision studies.