Kompaneyets equation refers to a non-relativistic, Fokker–Planck type, kinetic equation for photon number density with which photons interact with an electron gas via Compton scattering, first derived by Alexander Kompaneyets in 1949 and published in 1957 after declassification.[1][2] The Kompaneyets equation describes how an initial photon distribution relaxes to the equilibrium Bose–Einstein distribution. Kompaneyets pointed out the radiation field on its own cannot reach the equilibrium distribution since the Maxwells equation are linear but it needs to exchange energy with the electron gas. The Kompaneyets equation has been used as a basis for analysis of the Sunyaev–Zeldovich effect.[3]
- ^ Kompaneets, A. (1957). The establishment of thermal equilibrium between quanta and electrons. Soviet Journal of Experimental and Theoretical Physics, 4(5), 730-737.
- ^ Oliveira, G. E. F., Maes, C., & Meerts, K. (2021). On the derivation of the Kompaneets equation. Astroparticle Physics, 133, 102644.
- ^ Sunyaev, R. A., & Zeldovich, Y. B. (1970). Small-scale fluctuations of relic radiation. Astrophysics and Space Science, 7, 3-19.