Photomultiplier , interaction-induced

This method involves filling a container with an air sample of radon and transferring it to a laboratory for analysis. One of the most useful devices is the scintillation flask, known as the Lucas cell. This consists of a chamber whose walls are coated with a scintillating material such as silver-activated zinc sulfide. The cell is optically coupled to a photomultiplier tube to count the light pulses (scintillation) induced by the a-particles interacting with the zinc sulfide coating. The scintillation flask can be filled either by evacuation or by airflow using a... 

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