2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/222501We study the surface plasmon modes of an arbitrarily shaped nanoparticle in the electrostatic limit. We first deduce an eigenvalue equation for these modes, expressed in terms of the Dirichlet-Neumann operators. We then use the properties of these pseudo-differential operators for deriving the limit of the high-order modes.8 pages, 1 figure, to appear in: Journal of Physics AMathematical Physicstext