Section 6.1.1.1. Coherent (Rayleigh) scattering

An electromagnetic wave incident on a tightly bound electron is scattered coherently. For an incident wave of unit amplitude with the electric vector normal to the plane of the reflection x0y containing the incident and diffracted beams (Fig. 6.1.1.1 ), the amplitude of the scattered wave at a distance r is where is the classical radius of the electron (2.818 × 10⁻¹⁵ m).

Figure 6.1.1.1| top | pdf | Scattering by an electron. k0 and k are the incident and scattered wavevectors, respectively.

For a wave with the electric vector parallel to the plane x0y, the amplitude of the scattered wave is For unpolarized incident radiation with unit mean amplitude, the amplitude of the scattered wave is given by the Thomson formulaThe corresponding intensity of scattering per unit solid angle is for an unpolarized incident beam of intensity .