Title: radiant energy
Long Title: IUPAC Gold Book - radiant energy
DOI: 10.1351/goldbook.R05039
Status: current
Index: quantity

Definition
The total energy emitted, transferred or received as radiation in a defined period of time (\(Q=\int Q_{\lambda }  \ \mathrm{d}\lambda \)). It is the product of radiant power, \(P\), and time, \(t\): \(Q=P\ t\) when the radiant power is constant over the time considered.

Related Term
- radiant power: https://dev.goldbook.iupac.org/terms/view/R05046

Sources
- Green Book, 2nd ed., p. 30 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)
- ISO 31-05: 1992 (https://www.iso.org/iso/catalogue_detail.htm?csnumber=3635)
- PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2268 (https://doi.org/10.1351/pac199668122223)
- PAC, 1996, 68, 957. 'Glossary of terms in quantities and units in Clinical Chemistry (IUPAC-IFCC Recommendations 1996)' on page 988 (https://doi.org/10.1351/pac199668040957)

Other Outputs
- html: https://dev.goldbook.iupac.org/terms/view/R05039/html
- json: https://dev.goldbook.iupac.org/terms/view/R05039/json
- xml: https://dev.goldbook.iupac.org/terms/view/R05039/xml

Citation: Citation: 'radiant energy' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.R05039
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Accessed: 2026-06-13T02:54:39+00:00