Inelastic mean free path, electron, matter

The attenuation of the electron flux by matter is characterised by the inelastic mean free path between two successive shocks denoted X. The mean free path varies according to the kinetic energy of the electron for kinetic energy levels from 100 to 1000 eV, X varies between 0.5... 

The term exp [-2 RjlAj k)] describes the attenuation of the EXAFS amplitude caused by inelastic scattering processes experienced by the excited electrons outside of the absorbing atom. The mean free path Aj k) of electrons in condensed matter is rather small, typically between 5 andl 0 A. The k dependence of X is often linear. Experimental Xj k) curves are known for only very few substances. 

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