Liquid Scintillation Counting

In liquid scintillation counting (LSC) we use the process of luminescense to detect ionising radiation emit$ed from a radionuclide. Luminescense is emission of visible light of nonthermal origin. 1t was early found that certain organic molecules have luminescent properties and such molecules are used in LSC. Today LSC is the mostwidespread method to detect pure beta-ernitters like tritium and carbon-14. 1t has unique properties in its efficient counting geometry, deteetability and the lack of any window which the betaparticles have to penetrate. These properties are achieved by solving the sample to measure in a scintillation cocktail composed of an organic solvent and a solute (scintillator). Even if LSC is a weil established measurement technique, the user can run into problems and abasic knowledge of the deteetor and its different components is of fundamental importance in a correct use of the technique. The alm of this presentation is to provide the user with some of this fundamental knowledge