
7.3 Detection of Threat Materials (Explosives, Drugs, and Dangerous Chemicals)
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of soil moisture as measured with the BGO detector. e soil moisture content
may also be measured by measuring the hydrogen content. e hydrogen can
be detected by its captured gamma ray line at 2.2 MeV, which usually is a part
of a random background spectrum.
e dierence in carbon content between the soil and the TNT explosive
enables the possibility to detect the AP mine. Figure 7.52a shows the theo-
retical normal distributions of the carbon content in soil and from the mine
buried into the soil (Figure 7.52b). It can be seen that the two distributions
overlap ...