Cross-section and types of scattering
https://en.wikipedia.org/wiki/Cross_section_(physics)
dimensionality $\sigma \sim (cm)^2$
resonant scattering at high frequencies $\sigma \sim \frac{1}{\omega^2}$
Rayleigh scattering https://en.wikipedia.org/wiki/Rayleigh_scattering
$\sigma \sim \frac{1}{\omega^4}$