Development of a linear position-sensitive neutron detector

Abstract

A prototype for a position-sensitive linear neutron detector based on 6Li glass scintillator, light coupler and a stack of photomultipliers was experimentally investigated and numerically evaluated in computer simulations. The photomultiplier gain is electronically stabilized to assure high long-term stability. A new pulse processing method with a digital coarse preselection of three photomultiplier signals is developed. Thereby the effect of noise pulses is considerably reduced and the integral and differential linearity as well as the spatial resolution is improved. With the computer calculations various geometrical arrangements are considered and the influence of the light coupler thickness and of a smoothing parameter on the linearity and spatial resolution is discussed. Calculated and measured values for the linearity, resolution and time stability are presented. Promising preliminary results of pulse shape discrimination against γ rays are described.