Year
2001
Abstract
The use of digital signal processing (DSP) has become the standard for high-performance laboratory instruments for measurements in the field of nuclear spectroscopy. In all applications it offers greater stability, improved resolution and greater throughput at high count rates compared to analog or traditional designs. All of these improve the quality of the spectrum and the analysis results. Safeguards applications, especially the isotopic-ratio calculation, depend on the high resolution and stability of the MCA and detector for accurate results. Recently, advances in low-power DSP modules have made it possible to incorporate DSP in useable, portable instruments. A portable multichannel analyzer system consisting of a HPGe detector, with integral bias supply, and a MCA has been developed. This system includes all the benefits of digital processing in a complete instrument for spectroscopy. In addition, the unit includes a local display and keypad, to eliminate or significantly reduce the need for a PC in many field applications. When used with the associated \"intelligent\" HPGe detector system, the instrument monitors 18 operating parameters of the system, including detector temperature, to derive the overall system state of health. In addition, the unit provides authentication of the entire system and the collected data. The system has been tested using both liquid-nitrogen and electrically cooled detectors. The peak position and resolution have been measured using the commonly available mixed nuclide sources. Performance data for peak resolution and position vs countrate, peak resolution and position vs time, using Safeguards-quality HPGe detectors will be presented.