The shift in wavelength upon scattering of light from stationary electrons. The Compton effect, discovered by Compton Eric Weisstein's World of Biography in 1923, provided the final confirmation of the validity of Planck's quantum hypothesis that electromagnetic radiation came in discrete massless packets (photons) with energy proportional to frequency.
Compton Scattering, Compton Wavelength, Inverse Compton Effect, Klein-Nishima Formula, Photon
References
Griffiths, D. J. Introduction to Elementary Particles. New York: Wiley, p. 15, 1987.
Grometstein, A. A. "Compton's Shift." Ch. 11 in The Roots of Things: Topics in Quantum Mechanics. New York: Kluwer, pp. 293-306, 1999.
Williams, B. G. (Ed.). Compton Scattering: The Investigation of Electron Momentum Distributions. New York: McGraw-Hill, 1977.
