Compton scattering

1923

Compton scattering

The book of science

Tom Sharp

Arthur Holly Compton physics

Compton scattering

Compton wavelength

Inelastic scattering

Classical electromagnetic theory predicted that X-rays would not lose energy when scattered. The effect depends on the energy of the photon relative to the energy-equivalent of an electron. Compton scattering is inelastic. It happens when the energy of the photon is higher. Thomson scattering is elastic but happens only when the energy of the photon is much less than the mass energy of the particle (when the particle’s Compton wavelength is much less than the photon’s wavelength).

At the energy of visible light, photons can knock electrons from a surface. This, called the photoelectric effect, supported the concept that energy is quantized.

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