Abstract
The radiative decay of non-radiative surface plasmons excited by fast electrons on sinusoidally modulated Ag surfaces has been investigated systematically for different modulation heights. The position and half-width of the surface-plasmon dispersion of weakly modulated gratings are in agreement with theoretical values derived for smooth surfaces; for stronger modulated gratings, displacement and broadening of the surface-plasmon dispersion and multiple-scattering are found.