Mass-dependent channel electron multiplier operation

Abstract

This paper contains the results of measurements to determine the absolute counting efficiencies and pulse height distributions of a continuous channel electron multiplier (Spiraltron) used in the detection of hydrogen, argon, and xenon ions. The technique involves the post‐acceleration of 8‐eV ion beams to energies between 100 and 4000 eV. The absolute counting efficiency versus effective ion energy for the ions H₂⁺, A⁺, and Xe⁺ is given. The Spiraltron was operated in a marginally gain saturated mode to investigate the charge pulse distribution for the three ions H₂⁺, A⁺, and Xe⁺ at ion energies of 3 keV. The pulse height distribution for the light ion H₂⁺ peaked near an equivalent gain of 2×10⁷, while the distributions for the heavier ions displayed no significant peaks. This study suggests that discrimination between light and heavy ions may be accomplished in the energy range E<2 keV by utilizing continuous channel electron multipliers.