Radiation

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For other uses, see Radiation (disambiguation).

Radiation in physics is the process of emitting energy in the form of waves or particles. Various types of radiation may be distinguished, depending on the properties of the emitted energy/matter, the type of the emission source, properties and purposes of the emission, etc. When used by the general public, the word "radiation" commonly refers to ionizing radiation.

1 Radiation by type of emission
2 Radiation by source/cause of emission
3 Radiation by properties of emission
4 See also

[edit] Radiation by type of emission

Electromagnetic radiation, a stream of photons.
- Gamma radiation, which is high-energy electromagnetic waves.
- Ultraviolet radiation, also known as UV.
- Infrared radiation, also known as heat.
Gravitational radiation, a predicted consequence of general relativity.
Particle radiation, radiation by means of particles that have a rest mass.
- Alpha radiation, composed of the nuclei of helium-4 atoms.
- Beta radiation, consisting of energetic electrons or positrons.
- Neutron radiation

[edit] Radiation by source/cause of emission

Particle:
- Delta radiation
- Epsilon radiation

Electromagnetic:
- Cherenkov radiation, electromagnetic radiation by a particle moving through an insulating medium faster than the speed of light in that medium.
- Synchrotron radiation, radiation by a charged particle undergoing acceleration.
- Solar radiation, radiation emitted by the sun.
- Thermal radiation, emission of electromagnetic radiation by a hot object
- Hawking radiation, thermal radiation thought to be emitted by black holes due to quantum effects.

[edit] Radiation by properties of emission

Ionizing radiation, radiation with sufficient energy to cause ionization.
Non-ionizing radiation, radiation that does not carry enough energy to directly cause ionization.