Ionization of metastable neon by electron impact

The partial electron impact ionization cross section for metastable neon, Ne-*+, has been measured in the energy range from threshold to 200 eV. The crossed-beam experiment used a fast neutral target (both ground state and ground state plus metastable) formed by charge transfer between an 800 eV neon ion beam and neon gas or sodium vapour. The ionization cross section for the P-3(2) and P-3(0) metastable components, which are assumed to be equal, was placed on an absolute scale by utilizing the known ground-state cross section and assuming that the beam fractions of the mixed state were statistically distributed. The results are compared with previous experimental and theoretical work.