A threshold-photoelectron coincidence spectrometer using a single detector and time-of-flight analysis

A simple instrument is described for the coincidence measurement of two near-zero energy (threshold) electrons, which can be used for the study of double-photo-ionization processes. The threshold electrons are collected by means of the penetrating field technique and the coincidence measurements are performed using a single detector (channel plates). The application of time-of-flight techniques leads to much improved spectral resolution and yields information on the double-photo-ionization process.