A paraboloidal electrostatic reflector for molecularhyphen;beam timehyphen;ofhyphen;flight photoelectron spectrometers

摘要

We describe a design for a paraboloidal electrostatic reflector (PER) adapted for molecularhyphen;beam timehyphen;ofhyphen;flight (TOF) photoelectron spectrometers. The PER offers a nearly two orders of magnitude improvement in detection efficiency over standard linehyphen;ofhyphen;sight TOF detection. The energy resolution Dgr;E/Eis nominally about 0.02, but can be improved to about 0.005 (to a current limit of Dgr;E=10 meV) at some expense in sensitivity. The PER makes possible sensitive measurements for inherently weak ionization experiments. We have used our spectrometer in applications involving lowhyphen;power picosecond pulses, lowhyphen;density molecular clusters, and ionization through dissociative states.