Calculation of the output charge cloud from a microchannel plate

The imaging performance of microchannel plate (MCP) detectors of photons and charged particles depends on the angular and energy distributions of the electrons in the output charge cloud. Measurements of these distributions are sparse and do not cover the full range of MCP operating parameters (input current, bias voltage, electrode design, channel length and channel diameter). Our two dimensional Monte Carlo model of the avalanche process in a single microchannel yields the output energy distribution of electrons (EDOE) and angular distribution of electrons (ADOE) for arbitrary channel geometries. The model has been validated by comparison with the available experimental data and used to examine the (a) effects of current saturation and (b) novel output electrode geometries. (C) 2001 Elsevier Science B.V. All rights reserved.