Abstract
A comparison of energy distribution curves of Sr+ thermal ions emitted from SrO-W surface with the result of mass spectrometric thermal analysis of SrO-W system has been made. The distribution curves have been obtained by the technique of electrical differentiation of the retarding voltage curves in a method similar to Auger electron spectroscopy with a four-grid low energy electron diffraction optics. The distribution curves obtained at various temperatures in the range 1570 - 1919 K are almost Maxwellian, except for 1842 K where the curve is very broad. The result at 1842 K is probably due to the emission of Sr+ thermal ions from various work function surfaces. From the values of retarding voltages at maximum of energy distribution curves, work functions of surfaces, from where Sr+ thermal ions are emitted, are measured. The values of work functions are widely varied with the chemical forms of strontium on tungsten.
