low count rate detection
see also:
particle detection, radiation detection, neutron detection, Geiger–Müller counter, scintillation counter, scintillation tracker, scintillation detector
Using single ion counting, low levels of radiation can be detected and characterized. In the area of radiation safety and non-proliferation small amounts of unknown nuclear material can be detected and identified using its spectra signature. Examples are special nuclear material (SNM) and shielded highly enriched uranium (HEU).