Thomson cross section
Quick Summary
The Thomson cross section, symbolized as \u03c30, is a concept used in physics to describe the probability of photons interacting with matter through scattering, specifically when the photon's energy is much lower than an electron's rest energy. It is mathematically defined as \u03c30 = (8\u03c0/3) (e2/mc2)2, where e is the electric charge, m is the electron's mass, and c is the speed of light.1
This concept is named after J.J. Thomson, an English physicist who discovered the electron in 1897 and received the Nobel Prize for Physics in 1906. His work revolutionized the understanding of atomic structure. The Thomson cross section is a classical approximation for photon scattering, distinct from Compton scattering, which occurs at higher photon energies.21
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