Secondary Electron Emission Coefficient from Metal Deuteride Bombarded by Medium-Low-Energy Proton

Abstract:

The secondary electron emission coefficient γ has been measured for ZrD1.74 and TiD1.70 material bombarded with proton of energies between 20 and 220 keV. It is found that in the energy range the coefficient is proportional to the electron stopping power for each sample when the beam density is 20 nA/cm2, except that the proportion factor Λ is about 50% lager than the Sternglass theory for the clean deuteride in this situation. Layer of impurity molecule adsorbed on the surface of the sample influences the coefficient γ. It is when the energy of incident proton is 100 keV and beam density is 7 μA/cm2 that the coefficient γ and the factor Λ fall steeply in the first 100 seconds when the beam bombarded sample and then become steady gradually, and eventually they are in good agreement with the Sternglass theory.