Microchannel plate electron multiplier calibration using a discrete detector array

The performance of a microchannel plate electron multiplier (MCP) is known to vary with time and exposure to ions, the atmosphere, and other factors. Clearly the recognition of deterioration in experimental work is of great importance. In the present work the performance of an MCP is straightforwardly measured using a detector array integrated on a silicon chip and results presented. The objective of this work is not to accurately quantify the MCP gain distribution but rather to find the distribution shape to enable straightforward monitoring of variations in gain distribution and identification of conditions under which essentially all MCP output pulses are recorded. Thus, isotope ratios of high quality can be measured. This work further demonstrates the versatility of a discrete detector array developed at Aberystwyth. It enables straightforward remote monitoring of the MCP performance and is especially valuable in space-borne experiments. (C) Elsevier Science B.V.