SBIR-STTR Award

We propose to develop a battery powered portable monitoring system capable of collecting and analyzing gamma spectra for specific radionuclides in the field. The system will consist of a high resolution cadmium telluride array detector and a small multichannel analyzer and data logger. The proposed monitoring system builds upon the design of the Ludlum Model 2350 Data Logger which is quite rugged and can operate for extended periods of time on battery power. The data logger will be reconfigured as a small multichannel analyzer that will integrate under specific regions of interest and report results by isotope on a large LCD display. For large projects the instrument will have the capability of dumping its data to a notebook computer. The detector will consist of spectroscopy grade CdTe crystals in an array, with individual preamplifiers to preserve the detector resolution. The detector array should have a resolution of 5 - 7 KeV at a photopeak energy of 60 KeV which is sufficient to identify most nuclides, and is particularly effective for the low energy photopeaks associated with transuranic radionuclides. The CdTe detector operates at room temperature and does not require cooling. The research should lead to the development of a small, rugged gamma spectrometer capable of rapid isotope identification. The instrument should be suitable for safeguards and other field applications. As you know, AM has been operating under a beta-test of the new network-based/Windows-based AM Tracking System since 13 May 1994. The beta-test has allowed us to develop knowledge of and confidence in the new system while maintaining a a backup in the original PR Tracking. In keeping with the original implementation plan, the beta-test is now declared completed and maintenance of the original PR Tracking system will be discontinued immediately. Negotiators are no longer required to submit hard-copy corrections using the Tracking printouts. Updates are to be made to individual actions in real time, at a minimum on a daily basis.

Keywords:
Radiation Detector Gamma Spectrometer

A phase I feasibility study has been completed on the development of a portable gamma spectrometer with a high resolution cadmium zinc telluride array detector. After evaluation of several personal computer components for both speed and power consumption, it was determined that a 486 DX4 or later notebook style motherboard will allow the unit to function for 4 to 8 hours on one internal set of NiMH batteries. Remote monitoring capabilities were added as well, utilizing commercially available remote software and a digital camera. Phase I efforts also included the development of low power consuming prototype detector electronics and active filters, including Sallen-Key and Bessel types, used with limited sc=uccess to suppress the low energy tail of the photopeak inherent with the CZT crystal array detector with rise time discrimination electronics to suppress the low energy photopeak tailing. A user friendly graphical interface to the detection system will also be developed in the Phase II research. The resulting spectrometer package should prove to be a valuable tool for the international safeguards community.

Keywords:
Gamma Spectrometer Monitoring Cadmium Zinc Telluride Portable Safeguards