- A tube which detects and quantifies ionizing radiation, such as alpha particles, beta particles, or gamma radiation. Such a tube contains a gas mixture, such as methane and argon in a given proportion, and has a thin wire anode mounted along the axis of a cylindrical metal chamber which serves as the cathode. A potential difference which is slightly less than that required for electric discharge is maintained between the electrodes at all times. In this manner, the gas becomes ionized whenever said tube is exposed to a radioactive substance, however faint it may be, and the resulting current is amplified for output. Also called Geiger counter tube (1), Geiger-Müller counter tube (1), or Geiger-Müller tube (1).
- synonymGeiger counter