A positron microscope utilizes a time-of-flight adjustment and a beam gate to distinguish images produced by respective types of positronium events. If the time-of-flight of secondary electrons is approximately between 30 and 40 ns, then the electron image will represent prompt annihilations and parapositronium distributions in the target. For time-of-flight between 50 and 100 ns longer than the processing time of the electronic gating circuitry, the electron image will be a map of long-lived orthopositronium events.
Position microscopy