Optimal detector geometry to maximize light output and timing characteristics of fast scintillators

A Monte Carlo computer program has been developed to test different detector geometries in an effort to determine the shape that maximizes a figure of merit based on increasing the temporal resolution while retaining high sensitivity. Detector crystals shaped as truncated cones were examined with specular scattering from the crystal-air interface. On the basis of the results, two truncated cones with 20-mm base radius, 10-mm top radius, and 20-mm height were purchased and compared to existing 20-mm*20-mm*40-mm crystals and to the results in the literature. The temporal resolution obtained with the cone system is 222 ps FWHM with an intrinsic efficiency of 24%. The experimental results confirm the accuracy and usefulness of the computer model.<>