Elastic and Inelastic Electron Scattering at 20 and 60 eV from Atomic Cu

Abstract

Normalized differential and integral electron-impact cross sections for elastic scattering and for the excitation of the $^{2}D_{\frac{5}{2}}$, $^{2}D_{\frac{3}{2}}$, and $^{2}P_{\frac{3}{2},\frac{1}{2}}$ levels of atomic copper have been determined at 20 and 60 eV. An unexpectedly large cross section was found for the excitation of the $^{2}P_{\frac{3}{2},\frac{1}{2}}$ levels, which at certain angular and energy ranges surpasses the cross section for elastic scattering. The integral cross sections in units of ${10}^{\ensuremath{-}16}$ ${\mathrm{cm}}^{2}$ are elastic, 91.0 and 59.0; $^{2}D_{\frac{5}{2}}$, 1.85 and 0.36; $^{2}D_{\frac{3}{2}}$, 1.26 and 0.26; $^{2}P_{\frac{3}{2},\frac{1}{2}}$, 77.2 and 36.5, at 20 and 60 eV, respectively.