The extent to which the output of the @R05054@ is directly proportional to the incident @R05046@ at a given @W06659@ and at constant @I03255@ geometry.
Source: PAC, 1995, 67, 1745. (Nomenclature, symbols, units and their usage in spectrochemical analysis-XI. Detection of radiation (IUPAC Recommendations 1995)) on page 1750 [Terms] [Paper]