International
Tables for Crystallography Volume C Mathematical, physical and chemical tables Edited by E. Prince © International Union of Crystallography 2006 |
International Tables for Crystallography (2006). Vol. C. ch. 4.2, p. 242
Section 4.2.6.1.2. Thomson scattering by a free electron
D. C. Creaghb
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From classical electromagnetic theory, it can be shown that the fraction of incident intensity scattered by a free electron is, at a position r, from the scattering electron,
where
is the classical radius of the electron (= 2.817938 × 10−15 m). The factor
arises from the assumption that the electromagnetic wave is initially unpolarized. Should the wave be polarized, the factor is necessarily different from that given in equation (4.2.6.1)
.
Equation (4.2.6.1) is the basis on which the scattering power of ensembles of electrons is compared.