Calculation of the output charge cloud from a microchannel plate

The imaging performance of microchannel plate (MCP) detectors of photons an d charged particles depends on the angular and energy distributions of the electrons in the output charge cloud. Measurements of these distributions a re sparse and do not cover the full range of MCP operating parameters (inpu t current, bias voltage, electrode design, channel length and channel diame ter). Our two dimensional Monte Carlo model of the avalanche process in a s ingle microchannel yields the output energy distribution of electrons (EDOE ) and angular distribution of electrons (ADOE) for arbitrary channel geomet ries. The model has been validated by comparison with the available experim ental data and used to examine the (a) effects of current saturation and (b ) novel output electrode geometries. (C) 2001 Elsevier Science B.V. All rig hts reserved.