An ellipsoidal mirror time-of-flight photoelectron energy analyzer

A novel time-of-flight photoelectron energy analyzer that uses an electrostatic field to reflect and focus electrons has been designed and built. By means of high quality ellipsoidal grids, photoelectrons can be collected at high efficiency and focused onto a detector. The problems of space charge and extended electron sources are addressed in the context of the ellipsoidal mirror analyzer. This versatile spectrometer analyzes single and multiphoton ionization processes and operates over a wide energy range. The experimental data demonstrate the high collection efficiency. We have obtained good spectra at target densities of less than 10(-7) Torr. For six-photon ionization of xenon a gain of 36 has been achieved. (C) 1995 American Institute of Physics.