Studies on the detection of concealed objects using the neutron reflection method

The increment of reflected thermal and 1.45 eV resonance neutrons vs. the thickness of the reflector has been measured and described by an analytical expression. Macroscopic, Σβ, and microscopic, σβ, reflection cross sections averaged over the bulk reflector substances were deduced for some elements and compounds. It was found that the σβ values are additive even for bulk samples and so the σβmol could be given for some illicit drugs, explosives and hiding materials.

► The effect of reflector materials on the increment of neutrons were determined.
► Macroscopic and microscopic reflection cross sections averaged over bulk samples were determined.
► Simple analytical expression was given to describe the yield of reflected neutrons.
► The observed additive behavior in reflected neutrons rendered to characterize other materials.