Radiobiology > Physical Processes > Quanta > Alpha Particles

Alpha Particles

Alpha particles...

• Are large and positively charged
• Tend to cause ionizations and lose energy over a very short distance
• Are composed of two protons and two neutrons (i.e. a naked helium nucleus)
• Large size + relatively high charge prevent deep penetration of matter (blocked by dead skin or paper)
• Chronic exposure to inhaled alpha particles is a lung cancer risk
• Are important in the uranium decay series, of which radon is a product