Angular Distribution of Photoelectrons. I. Cadmium and Zinc Atoms at 584 and 1048 Å

Abstract

The distribution of photoelectron trajectories has been measured with unpolarized resonance emission from helium and argon, modulated atomic beams of cadmium and zinc, a sector‐focusing photoelectron energy analyzer, and digital counting and demodulation techniques. The autoionizing transitions at 1048 Å to produce ${\mathrm{Cd}}^{+}{}^2{S}_{\text{1/2}}$ and ${\mathrm{Zn}}^{+}{}^2{S}_{\text{1/2}}$ and the direct ionization at 584 Å to produce ${\mathrm{Cd}}^{+}{}^2{D}_{\text{5/2}}$ all result in electron‐trajectory distributions which are close to ${\cos }^2\theta$ with respect to the electric vector of the radiation. Ionization at 584 Å to produce ${\mathrm{Cd}}^{+}{}^2{D}_{\text{3/2}}$ results in an isotropic distribution. For cadmium the ratio of total cross sections to produce ${}^2{D}_{\text{5/2}}{\mathrm{\hspace{0.17em}/\hspace{0.17em}}}^2{D}_{\text{3/2}}\mathrm{is}\text{1.06\hspace{0.17em}±\hspace{0.17em}0.07}$ .