This paper presents a radioisotope-based concept for determining whether an anomaly in the ground contains an explosive material or not. Nitrogen-based explosives, commonly used in landmines, are rich in carbon, nitrogen and oxygen. Hydrogen is also present in the explosive material, but can be found as well in the mine casing (if plastic or wood). Moreover, explosive materials have a density that is higher than that of most organic materials, but lower than that of metals. All these features are employed in a detection concept that relies on the use of an isotopic source of neutrons. The amount of slowing-down of the source's fast neutrons, as they scatter to the thermal energy, is indicative of the hydrogen content. The enhancement of the intensity of fast neutrons, due to resonance scattering by carbon, nitrogen and oxygen, is indicative of their combined presence. Moreover, the photons that accompany neutron production, are Compton-scattered, providing an indication of the electron-density of the anomaly. These three measurements, contrasted against those obtained from the surrounding soil, are indicative of the presence or absence of a mine, or a mine-like, target.
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