Term: backscatter
https://doi.org/10.1351/goldbook.B00581

Definition:
Scattering of radiation in a generally backward direction. In the assay of radioactivity, it applies to the scattering of radiation into the radiation detector from any material except the sample and the detector. In light scattering, it is said to occur when the scattering angle, θ, is 180°. Conversely, forward scattering occurs when θ is 0°.

Related Terms:
1) scattering (http://doi.org/10.1351/goldbook.S05487-1).
2) assay (http://doi.org/10.1351/goldbook.A00470).
3) radioactivity (http://doi.org/10.1351/goldbook.R05092).
4) radiation detector (http://doi.org/10.1351/goldbook.R05054).
5) light scattering (http://doi.org/10.1351/goldbook.L03525).
6) scattering angle (http://doi.org/10.1351/goldbook.S05488).
7) scattering (http://doi.org/10.1351/goldbook.S05487-2).

Source: Orange Book, 2nd ed., p. 213 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'backscatter' 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.B00581

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