Absolute ionisation cross sections for electrons incident on O+, Ne+, Xe+and Ari+(i=1,...,5) ions

Abstract

Absolute ionisation cross sections for electrons incident on O⁺, Ne⁺, Xe⁺ and Ar¹⁺,..., Ar⁵⁺ ions have been measured at electron energies E_e between the ionisation threshold E_i and 830 eV. The measurements have been performed with crossed electron and ion beams. The comparison of the data for O⁺ and Ne⁺ with results of Aitken and Harrison (see ibid., vol.4, p.1176, 1971) and Dolder et al. (see Rep. Prog. Phys., vol.39, p.693, 1976), respectively, shows agreement within the combined experimental errors. The measured cross sections for ionisation of Arⁱ⁺ ions can be reproduced within +or-20% of the empirical formula sigma _i,i+1=1.4*10^-13((ln(E_e/E_i))/(E_eE_i))(eV)² cm² for the charge states i=1 up to i=5.