a line in a spectrum due to the absorption or emission of light at a discrete frequency.
An isolated bright or dark line in a spectrograph produced by emission or absorption of light of a single wavelength, generally corresponding to a specific shift in the energy of an electron moving from one orbital to another.
- Spectral luminous efficiency
noun 1. a measure of the efficiency of radiation of a given wavelength in producing a visual sensation. It is equal to the ratio of the radiant flux at a standard wavelength to that at the given wavelength when the standard wavelength is chosen so that the maximum value of this ratio is unity ((for […]
adjective 1. of or relating to a specter; ghostly; phantom. 2. resembling or suggesting a specter. 3. of, relating to, or produced by a spectrum or spectra. 4. resembling or suggesting a spectrum or spectra. adjective 1. of or like a spectre 2. of or relating to a spectrum: spectral colours 3. (physics) (of a […]
noun, Physics. 1. a series of lines in the spectrum of light emitted by excited atoms of an element, each line being related to the others in the series by a simple numerical equation and identified with a particular energy level of an atom of the element.
noun, Astronomy. 1. a category for classifying a star, as A star or G star, according to features of its spectrum, as its shape as a function of temperature and wavelength and its absorption spectrum, that indicate the surface temperature of the star and the presence of particular atoms or molecules in its outer layers: […]