electron emission
{{Short description|Ejection of an electron from the surface of matter, or atomic nucleus}}
{{one source |date=March 2024}}
In physics, electron emission is the ejection of an electron from the surface of matter,{{Cite web|url=https://www.electrical4u.com/electron-emission/|title=Electron Emission: What is it & Types of Electron Emission | Electrical4U|website=www.electrical4u.com}} or, in beta decay (β− decay), where a beta particle (a fast energetic electron or positron) is emitted from an atomic nucleus transforming the original nuclide to an isobar.
Radioactive decay
{{main|Beta decay}}
- In Beta decay (β− decay), radioactive decay results in a beta particle (fast energetic electron or positron in β+ decay) being emitted from the nucleus
Surface emission
{{main|Thermionic emission|Field electron emission}}
- Thermionic emission, the liberation of electrons from an electrode by virtue of its temperature
- Schottky emission, due to the:
- Schottky effect or field enhanced thermionic emission
- Field electron emission, emission of electrons induced by an electrostatic field
=Devices=
{{main|electron gun}}
- An electron gun or electron emitter, is an electrical component in some vacuum tubes that uses surface emission
Others
- Exoelectron emission, a weak electron emission, appearing only from pretreated objects
- Photoelectric effect, the emission of electrons when electromagnetic radiation, such as light, hits a material
See also
- Positron emission, (of a positron or "antielectron") is one aspect of β+ decay
- Electron excitation, the transfer of an electron to a higher atomic orbital