Potential and Kinetic Electron Ejection from Molybdenum by Argon Ions and Neutral Atoms

The yield of secondary electrons γₙ, from cleaned surfaces of polycrystalline molybdenum has been measured for argon neutral atoms (Ar⁰) in the energy range 500-2500 eV. The values of γₙ thus obtained are compared with γᵢ, the yield for argon ions previously determined. It is found that the rates of increase of γᵢ and γₙ with energy E are not equal in the region of kinetic ejection. The ratio (dγᵢdE)(dγₙdE) is 1.5. The result indicates that assumed models concerning the respective contributions of potential and kinetic ejection to the secondary electron yield at energies above 1000 eV should be modified.