The Compton Effect

The Compton effect, discovered in 1923 by the American physicist and educator Arthur Holly Compton, is an important manifestation of the absorption of X rays of shorter wavelengths. When a high-energy photon collides with an electron, both particles may be deflected at an angle to the direction of the path of the incident X ray. The incident photon, having delivered some of its energy to the electron, emerges with a longer wavelength. These deflections, accompanied by a change of wavelength, are known as Compton scattering.