The interaction of atomic particles with solid surfaces at intermediate energies I. Secondary electron emission

The electron emission from a number of metal and carbon targets bombarded by various positive ions is measured by a method employing a magnetic field to separate secondary electrons from scattered ions. Molecular ions are shown to produce emission approximately equal to that which would be produced by the individual atoms independently. Accurate measurements have been made of the energy distribution of secondary electrons. These are close to Gaussian. It is concluded that secondary electron emission is confined to the surface layers of the target atoms since no electrons possess energies close to zero.