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Emission spectrum, the spectrum of frequencies of electromagnetic radiation generated by molecular electrons making transitions to lower energy states •
Thermal emission, electromagnetic radiation generated by the thermal motion of particles in matter •
List of light sources, including both natural and artificial processes that emit light •
Emission (radiocommunications), a radio signal (usually modulated) emitted from a radio transmitter •
Emission coefficient, a coefficient in the power output per unit time of an electromagnetic source •
Emission line, or "spectral line", a dark or bright line in an otherwise uniform and continuous spectrum •
Emission nebula, a cloud of ionized gas emitting light of various colors •
Emission theory (relativity), a competing theory for the special theory of relativity, explaining the results of the Michelson-Morley experiment •
Emission theory (vision), the proposal that visual perception is accomplished by rays of light emitted by the eyes == Other uses ==