Term: scattering cross-section, \(\sigma_{\text{scat}}\)
https://doi.org/10.1351/goldbook.S05490

Definition:
The scattering coefficient per particle (cm2/particle); \[b_{\text{scat}}=n\ \sigma _{\text{scat}}\] where n is the number concentration of particles (particles cm-3) and σ scat is the scattering cross-section. bscat, the scattering component of extinction due to gas and particles, is measured in the atmosphere using a nephelometer. For a homogeneous atmosphere it is related in theory to the meteorological range (LV): LV = 3.9/bscat; bscat and babs represent the scattering and absorption coefficients per unit length for a light beam (of path length L) which has a spectral radiance (intensity) i0 incident on a sample of air and I is the transmitted spectral radiance (intensity), ln ( I 0 I ) = L ( b scat + b ab.

Related Terms:
1) scattering (http://doi.org/10.1351/goldbook.S05487).
2) coefficient (http://doi.org/10.1351/goldbook.C01124).
3) extinction (http://doi.org/10.1351/goldbook.E02293).
4) spectral radiance (http://doi.org/10.1351/goldbook.S05824).

Source: PAC, 1990, 62, 2167. 'Glossary of atmospheric chemistry terms (Recommendations 1990)' on page 2212 (https://doi.org/10.1351/pac199062112167)

Citation: 'scattering cross-section, \(\sigma_{\text{scat}}\)' 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.S05490

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