Method for Estimating Excess Kinetic Energy of Ionization Products in a Pulsed Ion Source

The decay of thermal ions, produced in the pulsed ion source of a 60° magnetic sector mass spectrometer, was investigated and compared with calculations. The increased ion decay observed for several positive and negative ions is attributed to kinetic energy in excess of their ambient thermal energy. The dependence of the method on experimental conditions and particle collision effect is briefly discussed.