Description:
The temporal change of the radial and axial dependence of emission in an impulsive Ne glow discharge was investigated, using two kinds of plane-parallel discharge tube, to study the effect of the anode structure on the initial growth mechanism of gas discharge. The discharge tubes consisted of a plane-disk cathode tube with a plane-mesh anode and a plane-disk cathode tube with a ring anode. Analysis of the data revealed that the space charge plays an important role not only in the stationary emission state but also at the initial emission stage, and depends on the anode structure; and the ambipolar diffusion takes effect some tens of microseconds after emission begins. The radial extent of the emission is sensitive to the anode structure, but the central axial extent of the emission depends on the gas pressure.