IUPAC > Gold Book > alphabetical index > R > radiant exposure, H
icon

IndexesDownload


PREVIOUSR05042NEXT
radiant exitance, Mradiant flux

radiant exposure, H

Radiant energy, Q, incident from all upward directions on an small sphere divided by the cross-sectional area of that sphere. SI unit is J m −2.
Notes:
  1. Equivalent definition: Irradiance, E, integrated over the time of irradiation.
  2. Mathematical definition: H = d Q / d S = ∫ t E ⁢ d t If Q is constant over the area, H = Q / S. If E, is constant over the time interval, H = E t.
  3. This term refers to a beam not scattered or reflected by the target or its surroundings. For a beam incident from all directions fluence (H o, F o) is an equivalent term.
Source:
PAC, 2007, 79, 293 (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 409
Related index:
IUPAC > Gold Book > math/physics > quantities
Interactive Link Maps
First LevelSecond LevelThird Level
GraphGraphGraph
Cite as:
IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook.
Last update: 2011-10-11; version: 2.3.
DOI of this term: doi:10.1351/goldbook.R05042.
Original PDF version: http://www.iupac.org/goldbook/R05042.pdf. The PDF version is out of date and is provided for reference purposes only. For some entries, the PDF version may be unavailable.
Current PDF version | Version for print | History of this term
picture