A comparison of the high count rate performance of several commercially available digital signal processors

Three commercial gamma-ray digital signal processors (DSPs), a Canberra InSpector 2000, an ORTEC DigiDART, and an X-ray Instrumentation Associates (XIA) Polaris system, coupled to a Canberra 2002C resistive-feedback preamplifier-equipped high-purity germanium (HPGe) detector, were performance tested to input rates of 440 kHz. This is a continuation study of work that was performed at the Idaho National Lab. In the first phase of this study the Canberra DSA2000 and the ORTEC DSPECPLUS were coupled to a transistor reset pre-amplifier (TRP) equipped HPGe gamma-ray detector and performance tested to input rates of 603 kHz. All spectrometers were evaluated on their throughput, stability and peak shape performance. The accuracy of their quantitative corrections for dead-time and pile-up were also tested. All of the tested units performed well at input rates that strain most analog spectroscopy systems