A device that detects ionizing radiation
by measuring the electric current generated when radiation, such as alpha
particles, beta particles, gamma
rays, or X-rays, ionizes the gas in the
chamber and therefore makes it electrically conductive. It contains two
electrodes with a variable potential difference between them. The passage
of radiation through the chamber ionizes the gas and the ions formed move
towards the charged electrodes. The current thus produced, which is amplified
in an associated circuitry, is proportional to the radiation intensity.
A similar process is used in a Geiger
counter, which detects and measures radioactivity.
| Principle of the ionization
Credit: European Nuclear Society
AND NUCLEAR PHYSICS