GEIGERCOUNTER
Geiger counter
A Geiger–Müller counter, also called a Geiger counter, is a type of particle detector that measures ionizing radiation. It detects the emission of nuclear radiation — alpha particles, beta particles, and gamma rays — by the ionization produced in a low-pressure gas in a Geiger–Müller tube, which gives its name to the instrument. In wide and prominent use as a hand-held radiation survey instrument, it is perhaps one of the world's best-known radiation instruments.The above text is a snippet from Wikipedia: Geiger counter
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