Microchannel Plate Detector Detection Efficiency to Monoenergetic Electrons Between 0.4 and 2.6 MeV

Abstract

An unshielded microchannel plate detector was irradiated by an electron beam to determine the detection efficiency of electrons to create a detector signal or counts. Tested electron energies spanned a range of 400 kiloelectron volts to 2.6 million electron volts (MeV). Detection efficiency was found to decrease as the electron energy increased and ranged between 0.18 and 0.05 counts per incident electron, at 0.4 and 2.6 MeV, respectively. Simulations of beam losses over the experimental geometry were performed with MCNP6, and found to be similar in magnitude and possess a similar dependence over incident electron energy as the experimentally determined beam loss from beam current measurements. Detection efficiency as a function of incident angle of the electrons was also tested and relatively insignificant changes were observed. For the three beam energies and angles tested, deviation of the measured detection efficiency was 16%–22% (basically within the overlapping error bars of each measurement).