Positron surface-state trapping induced by surface plasmon excitation under grazing scattering conditions

The inelastic scattering of slow positrons at metal surfaces is studied, with an emphasis on the trapping process into surface states. Surface plasmon excitation induces surface-state trapping of slow positrons. The energy and scattering angle dependence of the elastic scattering factor are calculated. Under grazing scattering conditions, surface-state trapping is an important inelastic process of low-energy positron diffraction.