What is scintillation ?
Name given to the production of light flashes emitted by luminescent substances when excited by high-energy radiation. The flashes can in turn liberate photoelectrons from photosensitive substances (for instance, caesium/antimony phosphors or some type of inorganic salt crystal such as NaI) (Tl activated); the photoelectrons are amplified by means of a photomultiplier tube before being converted into current pulses. The pulse height depends on the energy or the original gamma or corpuscular radiation, and the pulses can thus be sorted by means of a discriminator (pulse height analyzer). By using different discriminator channels the different nuclides in a mixture of isotopes can be determined either successively or simultaneously.
