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physical phenomena > process > physical process > optical process > radiation modification > radiation intensity modification > emission

emission
subject			fact

emission	has inverse process absorption
	has definition The process of transition of an electron from an outer orbit to an inner orbit around the nucleus results in a characteristic amount of energy being radiated (as line emission) that corresponds to the lost energy of the electron.
	is a kind of radiation intensity modification
radiation intensity modification	changes property intensity
optical process	has domain optics

Kinds of emission :

• bremsstrahlung (3 kinds, 13 facts) (deceleration radiation, free-free transition) - Radiation emitted or absorbed when a free electron is accelerated in the field of an atomic nucleus but remains in a hyperbolic orbit without being captured. Since bremsstrahlung is not quantized, photons of any wavelength can be emitted or absorbed. (Also called a free-free transition because the electron is free both before and after the transition.), Electromagnetic radiation given out by electrons interacting with the ions in an ionized gas.
• fluorescence (1 kind, 6 facts) - The absorption of a photon of one wavelength and reemission of one or more photons at longer wavelengths, especially the transformation of ultraviolet radiation into visible light., The emission of light at one wavelength, the green say, following absorption of light with a much shorter wavelength such as the ultraviolet. The UV photon parts with its energy by ejecting the electron into a high-energy level from which it cascades back down, releasing photons of lower energy and therefore longer wavelengths. A material which has this property is called a phosphor.
• radiative recombination (3 facts) - See radiative capture.
• recombination radiation (3 facts) - See radiative capture.
• spontaneous emission (3 facts) - Radiation emitted by an isolated body.
• stimulated emission (4 facts) (induced emission) - Radiation emitted by a body, such as an atom, when it is bombarded by radiation. The stimulated radiation has the same wavelength and direction as the bombarding radiation.