selfemission
Self-emission is the emission of energy by a system that originates from its own internal energy content, rather than from external excitation. It is commonly discussed in radiometry and spectroscopy as radiation produced by a body at nonzero temperature or by a quantum system returning from an excited state.
Thermal emission, or incandescence, occurs when a material is heated. Its spectrum follows Planck’s law and
Spontaneous emission is a quantum process in which an excited state decays to a lower energy level
Luminescent emission can also be viewed as self-emission when luminescent centers emit after an excitation source
Measurement and analysis: Self-emitted radiation is quantified through radiometry and spectroscopy. Key quantities include spectral radiance,
Applications and relevance: Self-emission underpins thermal imaging, incandescent lighting, and astrophysical observations, where the observed light