1001 REACTIONS OF THE Ar AND Kr ION DOUBLETS

Abstract

Ionization probability curves for Ar and Kr have been examined up to 1.5 eV above the ionization threshold using an electrostatic electron selector. Structure is observed between the Kr⁺ "ground" doublet levels and beyond the Ar⁺J = 1/2 level.Some of this structure is found to affect the 1001 collision cross section for these ions, which were measured in the primary ion energy range of 500–1 300 eV. The cross section for the J = 1/2 state is found to be larger than that for the J = 3/2 state in the case of Ar, while the reverse appears to be true for Kr.