surface approximation energy

https://doi.org/10.1351/goldbook.09370

Simplification of calculations involving the energy of an ion passing through a solid sample, where the energy of the ion at the surface is used in place of a properly averaged energy.

Note: This approximation is used to determine the energy at which scattering cross sections (see elastic scattering cross section, inelastic scattering cross section) or stopping cross sections, or both, are evaluated.

Source:
PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1833 (https://doi.org/10.1515/pac-2019-0404)