Figure 3.

Secondary electron spectrum of 500 eV electrons incident on a tungsten surface. The elastic peak is associated with LEED and the plasma loss peaks are associated with the creation by the incident electron of collective excitations of the valence electrons. These also emerge from the solid in inelastic LEED beams. The spectrum shown is taken with a large area detector and hence incorporates results from several diffracted beams. The Auger peaks associated with the tungsten itself and a carbon contaminant on the surface are shown in the derivative spectrum (Inset). [After Duke and Park (32) with permission.]