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Watson, Scott Avery

Publications and source records attributed to Watson, Scott Avery.

Identification of Material Type and Thickness Using Combined X-ray and Fast Neutron Radiography

Material identification (ID) using radiography is a problem that has implicitly existed since the discovery of the X-ray. Since 9-11, this problem has received renewed attention for homeland security applications of the generic, “what is in the box?” type1. Examples of items potentially in the box include: roadside bombs, nuclear weapons, contraband shipments and the like. In these cases, the “what” can include: explosives, projectiles, fissile material, or drugs. Here we investigate the ability of 60Co gamma-rays, 14MeV neutrons, and their combination to tease apart information about density, thickness and atomic number of items in the box. That information subset can be combined with other types of independent information (e.g. neutron and gammaspectroscopy, intelligence, photographs etc.) to assert a more complete picture of what, exactly, is in the box? That more complete information set can form the basis for actions including: remote detonation, evacuations, disablement, detention, search, arrest etc.

36 MATERIALS SCIENCE↗

Radiation sensitive paint and application thereof

A camera is used in conjunction with storage phosphor paint, configured to examine a surface. The surface is coated with storage phosphor paint in some embodiments. The camera is configured to image the surface coated with the storage phosphor paint, eliminating requirement of fast relaxation times associated with conventional scanners.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Technique for constructing high gradient insulators

A process for constructing a high-tensile strength, high-gradient insulator (HGI) may include stacking alternating layers of conductors and insulators, and vacuum pressure potting the stacked layers onto an insulating rod. The process may also include post machining the stacked layers to form a complete assembly of the HGI.

Watson, Scott Avery↗

PHOENIX Electrostatic Design

PHOENIX (Portable, High-efficiency, Optimal ENergy Imaging X-rays) is a quasi-DC, electrostatic, vacuum-diode designed as a portable x-ray source with national defense and commercial applications. The patent-pending PHOENIX concept combines a megavoltage, Cockroft-Walton voltage multiplier with a Van de-Graaff electrostatic charge-storage dome to create a vacuum-diode suitable for x-ray production. Naturally this structure must minimize internal electric fields to reduce electrical breakdown while simultaneously reducing size and weight to enhance portability. In this paper we describe the optimization process and model results obtained using the COMSOL multi-physics code. We describe three models: a prototype model built to demonstrate the PHOENIX concept as part of Laboratory Directed Research and Development (LDRD) Mission Foundation Research (MFR) Phase-I , a “back-of-the-envelope” design used as a starting point for further COMSOL optimization, and finally, the optimized geometry implemented in the MFR Phase-II. In all cases compromises resulting from cost, schedule, and manufacturing constraints were taken into account as the design progressed.

42 ENGINEERING↗