Forward optical glory

Abstract

Forward optical glory effects in Mie scattering are displayed here for the first time to our knowledge. These effects include regular oscillations in Mie efficiency factors and characteristic deviations from zero polarization in near-forward scattering, which are observable for real refractive indices near 2 and 2. Complex angular momentum theory predicts the period of oscillation correctly and shows the important role played by surface waves with shortcuts through the sphere. Three possible types of experiment for detecting the forward glory are proposed, involving measurements of extinction, radiation pressure, and polarization in near-forward scattering.