Measurement of product rotational alignment in associative-ionization collisions between polarized Na(3p) atoms.

Abstract

We have studied the effect of reactant Na(3p) polarization on the rotational angular momentum alignment of product ${\mathrm{Na}}_{2}$${\mathrm{}}^{+}$ ions arising from associative-ionization (AI) collisions. Our results show that sensitivity of the AI rate constant to initial atomic polarization persists even when all hyperfine states are populated with broadband (3 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$) pulsed laser excitation of Na${(\mathrm{}}^{2}$${P}_{3/2}$) and that the spatial distribution of product rotational angular momentum vectors is anisotropic. We discuss a qualitative description of the collision process consistent with our measurements which indicates that \ensuremath{\sigma}-orbital symmetry is preferred to \ensuremath{\pi}-orbital symmetry as the colliding partners approach.