Digital waveform analysis techniques for pixelated semiconductor detectors

A digital signal processing system for pixelated mercuric iodide and cadmium zinc telluride gamma detectors has been developed to explore the benefits of pulse analysis based on digital waveform acquisition. The system is capable of collecting 15 digital waveforms per radiation interaction event simultaneously. The precision of these measurements is enhanced through the use of digital filters optimized for unique signal features. Detailed analysis of waveforms from a set of adjacent pixels reveals energy, timing, and interaction position information. Current efforts focus on software-based techniques to characterize single and multiple pixel events including charge sharing, x-ray escape, and Compton scatter. The ability to distinguish between these events is a critical component of event reconstruction algorithms used in many radiation imaging applications.