A high resolution delay line readout for microchannel plates

Abstract

Investigations are reported of delay line configurations used to encode photon event locations in microchannel plate (MCP) detectors. Several delay line schemes of planar and multilayer structure are discussed. The importance of the delay line substrate material is examined, and it is shown that the raw signals from delay lines are narrow (about 3-4 ns FWHM). The factors determining the delay line resolution are evaluated, and it is demonstrated that these are in agreement with measurements. Resolutions of about 18-micron FWHM have been achieved. Measurements of the linearity of the delay line readout show that event centroid locations deviate from perfect linearity by less than 50 microns, even with the very simple anode fabrication methods employed. The image stability has also been evaluated and it is shown that image shifts are less than one resolution element over a period of two months.