Simulation studies for a new high-resolution positron tomograph

This paper reports on the performance characteristics of a multi-ring, high-resolution positron tomograph, investigated using Monte Carlo simulation methods. The tomograph will consist of four rings of 600 BGO crystals (3mm x 10mm x 30mm) per ring, ring diameter of about 62 cm, and removable inter-ring septa. The simulations emphasize modeling the detector response accurately. Because of the narrow crystal width (3mm) and the absence of inter-crystal septa, inter-crystal gamma-ray penetration and Compton scattering significantly affects the tomograph's overall spatial resolution, more so for off-axis regions. The studies allow the prediction of the proposed tomograph's sensitivity, as well as the distribution of the primary and scatter components. These studies should prove very valuable in determining the optimal design and configuration of the proposed tomograph