eng
emissivity
ratio of the energy radiated by an emissive surface relative to that of an ideal blackbody source at the same temperature
Note 1 to entry: It is generally related as a function of wavelength or frequency, emissivity values range from 0 to 1.
Note 2 to entry: This entry is adapted from Reference [12].
[SOURCE: ISO/TS 19124-1:2023, 3.12]