Particle and Electromagnetic Radiation
Decay of radionuclides results in the production of various forms of radiation. Radiation can occur as particles or as electromagnetic waves. Typical examples of particle radiation include alpha (α) particles, beta (β) particles, and neutrons. Alpha particles are energetic helium nuclei. They have a +2 charge and a mass of 4 amu. Beta particles are electrons. They can have either a -1 or +1 charge and have a very small mass. (β particles with a +1 charge are referred to as positrons.)
Electromagnetic radiation is composed of photons. Typical examples of this include x-rays and gamma-rays. X-rays are produced from transitions of electrons between electron orbitals. Gamma-rays are produced by transitions of nucleons in the nucleus.
Ionizing radiation is radiation composed of particles that individually carry enough kinetic energy to liberate an electron from an atom or molecule, thus ionizing it. Examples of ionizing radiation include cosmic rays, alpha particles, beta particles, gamma rays, and x-rays. We will be focusing on ionizing radiation, since it is this type of radiation that is used in detecting nuclear material.
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