中低能质子致金属氘化物二次电子发射系数研究

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

摘要:

测量了中低能质子致氘化钛和氘化锆二次电子发射系数。结果表明，20 nA/cm2束流下各二次电子发射系数与其电子能损近似成正比，比例因子Λ较Sternglass理论值偏大约50%，表面吸附层影响二次电子发射系数。束流密度为7 μA/cm2的100 keV质子束长时间测量时，二次电子发射系数γ和正比例因子Λ在前100 s内快速下降并逐渐稳定至理论值。

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.