spectral radiant power, Pλ 

https://doi.org/10.1351/goldbook.S05828
The radiant power at wavelength λ per unit wavelength interval. The SI unit is W m−1, but a commonly used unit is W nm−1.
Source:
PAC, 1996, 68, 2223. (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2276 [Terms] [Paper]
See also:
PAC, 1985, 57, 105. (Names, symbols, definitions and units of quantities in optical spectroscopy (Recommendations 1984)) on page 112 [Terms] [Paper]
Citation: 'spectral radiant power' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.S05828 RIS BibTex EndNote
Div. IIIPDFTextXMLJSONQuantity
Last revised: February 24, 2014