How is "ionization" defined in the context of radiation detection?

In the context of radiation detection, ionization is defined as the process by which radiation ejects electrons from atoms, resulting in the formation of charged particles. When radiation, such as alpha particles, beta particles, or gamma rays, interacts with matter, it has enough energy to overcome the binding energy of electrons within atoms. This interaction leads to the removal of electrons from their atomic orbits, creating positive ions (the remaining atom) and negative ions (the ejected electrons). This ionization process is fundamental to how various radiation detection devices operate, as these charged particles can be measured and counted to assess the presence and intensity of radiation.

The ability of radiation to ionize atoms is a key principle behind many detection methods, including Geiger-Müller counters and ion chambers, where the generation of charged particles is used to produce measurable electrical signals corresponding to the level of radiation exposure.