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We have developed a precise airborne temperature-sensing technology to detect buried objects for use by law enforcement. Demonstrations have imaged the sites of buried foundations, walls and trenches; mapped underground waterways and aquifers; and been used to locate underground military objects. Our patented methodology is incorporated in a commercially available, high signal-to-noise, dual-band infrared scanner with real-time, 12-bit digital image processing software and display. Our method creates color-coded images based on surface temperature variations of 0.2°C. Unlike other less-sensitive methods, it maps true (corrected) temperatures by removing the (decoupled) surface emissivity mask equivalent to 1°C or 2°C; this mask hinders interpretation of apparent (blackbody) temperatures. Once removed, we are able to identify surface temperature patterns from small diffusivity changes at buried object sites which heat and cool differently from their surroundings. Objects made of different materials and buried at different depths are identified by their unique spectral, spatial, thermal, temporal, emissivity and diffusivity signatures. We have successfully located the sites of buried (inert) simulated land mines 0.1 to 0.2 m deep; sodcovered rock pathways alongside dry ditches, deeper than 0.2 m; pavement covered burial trenches and cemetery structures as deep as 0.8 m; and aquifers more than 6 m and less than 60 m deep. Our technology could be athpted for drug interdiction and pollution control. For the former, we would locate buried tunnels, underground structures built beneath typical surface structures, mof-tops disguised by jungle canopies and covered containers used for contraband. For the latter, we would depict buried waste containers, sludge migration pathways from faulty containers and the juxtaposition of groundwater channels, if present, nearby. Our precise airborne temperature-sensing technology has a promising potential to detect underground epicenters of smuggling and pollution. BACKGROUND AND TECHNICAL APPROACHThe first successful demonstration of the precise temperature survey technology recently adapted for buried land mine detection was for geothermal resource investigations in 1977. Predawn surface temperature patterns were spatially correlated with sub-surface heat flow anomalies, soil moisture differences and variations in solar heat retained by near-surface rock tcroJ2 A 2 square km aquifer was depicted by the corrected thermal imagery. The aquifer was covered by more than 6 m of soil and was less than 60 m deep. See Figure 1 and Figure 2.Other applications of the technology were conducted at the Mercury Nevada Test Site for treaty verification. We investigated the surface temperature signatures near "ground zero" before and after an underground nuclear explosion. Soil "fluffmg" changed the soil thermal diffusivity and consequently the heating and cooling properties of near-surface materials near "ground zero." All else being equal, the ground nearby had a different temperature variation with...

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The newest generation of Gas Cherenkov Detector (GCD-3) employed in Inertial Confinement Fusion experiments at the Omega Laser Facility has provided improved performance over previous generations. Comparison of reaction histories measured using two different deuterium-tritium fusion products, namely gamma rays using GCD and neutrons using Neutron Temporal Diagnostic (NTD), have provided added credibility to both techniques. GCD-3 is now being brought to the National Ignition Facility (NIF) to supplement the existing Gamma Reaction History (GRH-6m) located 6 m from target chamber center (TCC). Initially it will be located in a reentrant well located 3.9 m from TCC. Data from GCD-3 will inform the design of a heavily-shielded "Super" GCD to be located as close as 20 cm from TCC. It will also provide a test-bed for faster optical detectors, potentially lowering the temporal resolution from the current ∼100 ps state-of-the-art photomultiplier tubes (PMT) to ∼10 ps Pulse Dilation PMT technology currently under development.

This paper presents a framework for designing the driving functions of an array of radiating elements given a scalar representation of the desired propagating field at a finite number of remote spatial locations. Based on a point source propagation model in a homogeneous media, the relationship between the driving functions and the resulting field leads to a system of linear equations in the frequency domain. A least-squares solution to the inverse problem is obtained by solving the system of linear equations for the unknown array driving functions. The proposed framework is suitable for designing array driving functions that could be used to generate "source-free" (homogeneous) solutions to the wave equation. This paper focuses on the use of the proposed technique for calculating array driving functions for generating localized wave energy. Two cases are discussed; one based on a source-free solution to the wave equation, and the other based on a numerical traveling impulse function. The results are compared to the beam generated by driving the array uniformly with a continuous-wave (ew) signal.