particle radiation

physics

Also known as: corpuscular radiation, particulate radiation

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Last updated

June 17, 2026

Quick Summary

Radiation is energy in motion. It can be electromagnetic, like light or X-rays, traveling at the speed of light, or particulate, like electrons or protons, traveling at speeds less than light but still very fast.1

Types of Radiation

Electromagnetic Radiation: This includes radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays. These forms have no rest mass.1
Matter Rays (Particulate Radiation): These are particles like electrons, protons, and neutrons that have mass when at rest. When traveling at high velocities, they are considered radiation.1

Interaction with Matter

All radiation interacts with matter. Ionizing radiation, which includes particulate radiation and high-energy electromagnetic radiation like gamma rays and X-rays, can produce ions in matter. This ionization can damage biological tissues by affecting DNA and proteins.2

Sources of Radiation

Radiation can be natural, such as cosmic rays or terrestrial radiation, or man-made, from sources like medical procedures, nuclear power plants, or atomic bombs.2

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chemical analysis
X-ray emission
…atom with electrons, protons, alpha particles, or another type of particles. The vacancy also can be created by absorption of X-ray radiation or by nuclear capture of an inner-shell electron as it approaches the nucleus. Often the bombardment is sufficiently energetic to cause the inner orbital electron to be completely…
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…atom with electrons, protons, alpha particles, or another type of particles. The vacancy also can be created by absorption of X-ray radiation or by nuclear capture of an inner-shell electron as it approaches the nucleus. Often the bombardment is sufficiently energetic to cause the inner orbital electron to be completely…
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radiation
Treating cancer and other diseases with highly energetic forms of ionizing radiation
…and gamma rays, densely ionizing particles—neutrons, protons, mesons, alpha particles, and heavy ions, for example—have been used increasingly to treat cancer and other lesions. Such high-LET radiations (see above The passage of matter rays: Linear energy transfer and track structure) offer potential advantages over conventional X rays and gamma rays…
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…and gamma rays, densely ionizing particles—neutrons, protons, mesons, alpha particles, and heavy ions, for example—have been used increasingly to treat cancer and other lesions. Such high-LET radiations (see above The passage of matter rays: Linear energy transfer and track structure) offer potential advantages over conventional X rays and gamma rays…
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radiation measurement
Organic scintillators
…the direct detection of charged particle radiations. They are seldom used to detect gamma rays because the low average atomic number of these materials inhibits the full energy absorption needed for spectroscopy. The average atomic number is not greatly different from that of tissue, however, and plastic scintillators have consequently…
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…the direct detection of charged particle radiations. They are seldom used to detect gamma rays because the low average atomic number of these materials inhibits the full energy absorption needed for spectroscopy. The average atomic number is not greatly different from that of tissue, however, and plastic scintillators have consequently…
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poison
Ionizing radiation
Alpha particles, beta particles, neutrons, and positrons are examples of particulate ionizing radiation. Gamma rays and X rays are electromagnetic ionizing radiation.
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Alpha particles, beta particles, neutrons, and positrons are examples of particulate ionizing radiation. Gamma rays and X rays are electromagnetic ionizing radiation.
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