The four types of radiations
The effects of particles (or radiations) depend primarily on their charge and on their mass. 1) Electrically charged particles (such as alpha and beta) lose energy by ionising atoms they come in contact with, whereas neutral particles (neutrons or gamma rays) lose their energy by colliding with electrons or nuclei, thus potentially causing indirect ionisation. 2) The relative masses of the different types of radiation are substantially different, with the alpha particle weighing nearly 7,300 times more than the beta particle (either an electron or a positron). 3) Neutrons and, to a lesser degree, alpha particles, are the two types of radiation made of nucleons able to produce changes within the nucleus.