Last revised by Daniel J Bell on 2 Mar 2020

Ionization is the principal means by which ionizing radiations dissipate their energy in matter. In this process the orbital electrons absorb energy from the incident photon, resulting in ejection of that electron, leaving the atom positively charged (positively ionized). 

In tissue this process can damage important molecules such as DNA, inducing detrimental biological effects, which may only become apparent after a period of time (latent period) that varies from minutes to weeks to years.

An ionized atom and a dislodged electron constitute an ion pair.

ADVERTISEMENT: Supporters see fewer/no ads