Impact parameter dependence of plasmon excitations in cylindrical nanostructures

We describe the bulk and surface plasmon excitations in cylindrical nanostructures by the impact of external charged particles. We study the average number of excited plasmons for different trajectories of the particle as a function of the impact parameter, using a quantum-mechanical formulation. This generalizes previous calculations obtained with null impact parameter. In particular, we study the case of wires at nanoscale dimensions.