Geiger-Müller Tube or G-M-tube is the sensing element of the Geiger Counter instrument used to detect ionized radiation.
It is a gaseous ionization detector and uses the Townsend avalanche phenomenon to produce an easily detectable electronic pulse, as low as an ionized phenomenon due to a radiation particle. It is used to detect gamma radiation, X-ray, and alpha and beta particles. It can also be adapted to detect neutrons.
