Simulation of Compton camera imaging with a specific purpose Monte Carlo code

A specific purpose Monte Carlo model that treats the physical processes of image formation in Compton cameras is presented. Features of the model include: detailed Compton scattering physics, including incoherent scattering functions and Doppler broadening; multiple scattering; and peak detector response functions. Calculation efficiency is enhanced by making every history result in a partial success through the extensive use of pathway sampling variance reduction techniques. The code was benchmarked to data obtained from a prototype camera using CdZnTe and silicon room-temperature detector technology. Reasons for observed discrepancies between the simulation model and experiments are explored. Implicit assumptions, related to our implementation of pathway sampling, appear to be the greatest source of error.