Klein-Nishina formula

proper noun

A formula for the differential cross section of photons scattered from a single free electron, calculated in the lowest order of quantum electrodynamics: (dσ)/(dΩ)=1/2r_e²(λ/(λ'))²[λ/(λ')+(λ')/λ- sin ²(θ)], where r_e is the classical electron radius, λ/λ' is the ratio of the wavelengths of the incident and scattered photons, and θ is the scattering angle (0 for an undeflected photon).

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Meanings

proper noun
  1. particlenatural sciencesA formula for the differential cross section of photons scattered from a single free electron, calculated in the lowest order of quantum electrodynamics: (dσ)/(dΩ)=1/2r_e²(λ/(λ'))²[λ/(λ')+(λ')/λ- sin ²(θ)], where r_e is the classical electron radius, λ/λ' is the ratio of the wavelengths of the incident and scattered photons, and θ is the scattering angle (0 for an undeflected photon).

Origin

Named after Oskar Klein and Yoshio Nishina who derived the equation in 1928.

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Cite this entry
APA

Klein-Nishina formula. (n.d.). In WatkinsX Dictionary. Retrieved November 5, 2026, from https://dictionary.watkinsx.com/word/Klein-Nishina%20formula

MLA

“Klein-Nishina formula.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/Klein-Nishina%20formula. Accessed November 5, 2026.

Chicago

WatkinsX Dictionary, s.v. “Klein-Nishina formula,” accessed November 5, 2026, https://dictionary.watkinsx.com/word/Klein-Nishina%20formula.

Source: Klein-Nishina formula on Wiktionary, CC BY-SA 4.0.