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Inner-shell Ionization Cross-section:

For quantitative simulation of characteristic x-ray or Auger electron intensities it is essential to have absolute ionization cross-section values. Although there is a lot of literature extensively dealing with measurements [Pow76] for and calculations of electron impact ionization cross sections, the large deviations between different ICS-measurements as well as the numerous models proposed by various authors show, that a satisfying solution of both measurement and calculation of inner-shell ionization cross-section has not yet been found.

In SESAME, a parameterization of a formula proposed by Hutchins [Hut74] published by Pouchou [Pou93] and a classically calculated expression by Gryzinski [Gry65] are implemented.

The formula by Pouchou is:

 

with and e is the Euler's constant. The parameters for the K-shell is:

The parameters for the L-subshells and the M-subshells are:

The expression from Gryzinsky, mainly valid for K-shell ionization, is:

 

The differential cross section for inner shell ionization, which describes the energy loss has also been proposed by Gryzinsky:

 

Further information about inelastic scattering can be found in the review papers of Ding [DS89] and Powell [Pow76] and in the CEC--Vienna Report by Horst Wagner [Wag94]. A detailed theoretical description of the inelastic scattering processes may be found in the book of Schattschneider [Sch86].


Horst Wagner
Tue Mar 19 10:24:55 MET 1996