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Brusseau, Charles A.

Publications and source records attributed to Brusseau, Charles A..

5 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2013

Screening portal, system and method of using same

A portal, system and method for screening an object for a target substance is provided. The portal includes an inflatable bladder expandable to form a test space for receiving the object and a plurality of nozzles positioned about the inflatable bladder. The nozzles are in fluid communication with a fluid source for directing air over the object whereby samples are removed from the object for examination. A collector is operatively connected to the inflatable bladder for collecting the samples removed from the object. A detector is operatively connected to the collector for examining the removed samples for the presence of the target substance. At least one preconcentrator may be operatively connected to the collector for concentrating the samples collected thereby.

47 OTHER INSTRUMENTATION↗
DOE OSTI2012

Design and Characterization of a Sodium Iodide (NaI) Array for Coincidence Measurements

An array of sodium iodide detectors (NaI) was constructed to record time-correlated gamma ray measurements. The NaI Array consists of twelve 2×4×16-inch detectors. When the array is placed close to an inspected object, this arrangement provides high efficiency for gamma ray detection, particularly for high-energy gamma rays. Data are collected in time-tagged, list-mode format, which is suitable for the application of a variety of coincidence analysis methods. Automated energy calibration of each detector is accomplished by utilizing gamma radiation from thoriated welding rods that are embedded in the system. The energy resolution of spectra that are produced by the NaI array is 7.3% at 662 keV. The data are processed to sum gamma-ray energies for simultaneous detections in adjacent detectors, which are dominated by the escape of scattered photons from one detector and subsequent absorption in an adjacent detector. When data are processed in this way, the photopeak efficiency exceeds 20% over the range 400 keV to 10 MeV; the total efficiency, which includes the Compton continuum and single and double escape peaks, exceeds 70% over this energy range. Utilization of time correlations enables isolation of spectral features that are associated with the same decay cascade or fission event. Characterization of the response of the NaI Array to both gamma rays and neutrons with the Gamma Detector Response and Analysis Software (GADRAS) enables accurate computation for virtually any radiation sources.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2012

PVT-NG Sensor Final Report

This document is a final report for the polyvinyl toluene (PVT) neutron-gamma (PVT-NG) project, which was sponsored by the Domestic Nuclear Detection Office (DNDO). The PVT-NG sensor uses PVT detectors for both gamma and neutron detection. The sensor exhibits excellent spectral resolution and gain stabilization, which are features that are beneficial for detection of both gamma-ray and neutron sources. In fact, the ability to perform isotope identification based on spectra that were measured by the PVT-NG sensor was demonstrated. As described in a previous report, the neutron sensitivity of the first version of the prototype was about 25% less than the DNDO requirement of 2.5 cps/ng for bare 252 Cf. This document describes design modifications that were expected to improve the neutron sensitivity by about 50% relative to the PVT-NG prototype. However, the project was terminated before execution of the design modifications after portal vendors demonstrated other technologies that enable neutron detection without the use of 3 He. Nevertheless, the PVT-NG sensor development demonstrated several performance goals that may be useful in future portal designs.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗