Design and simulation of a semiconductor detector-based Compton imaging system with efficiency analysis

Abstract

Compton cameras have become widespread in recent years because it uses electronic collimators. One or more scatterer detectors and an absorber detector make up the Compton camera, which is sensitive to the energy and location of scattered gamma rays. It predicts the distribution of gamma-ray sources by reflecting all valid events in the image space using conical surfaces. Compton cameras are designed for specific applications and image reconstruction using various methods. Based on studies of the efficiency of the Compton camera, the current work provides a novel detector design that includes scatterer and absorber detectors. The Compton imaging system is simulated using the GEANT4 toolkit. In addition, this research uses an analytical method to reconstruct the Compton camera image. The method used for analytical reconstruction in the Compton imaging system differs slightly from the simple restoration methods used in other imaging systems. In the analytical method, the equation related to the data reflected by the image must be solved to reconstruct the image directly. In this method, C + + code required development to reconstruct images using the Compton camera. According to the results, using the analytical method to identify the best circumstances and the parameters impacting efficiency, the value of FWHM achieved was 3.7 mm with an angular uncertainty of about 2.7 at an energy of 0.662 MeV. Furthermore, the value of FWHM was decreased by 0.7 mm, compared to another (experimental) design that employed the analytical image reconstruction approach.