Spatial Distributions of Electron Parameters and Glow of Hollow Cathode Plasma Discharge in Noble Gases (He, Ne, Ar, Xe)

Studies have been conducted on a discharge with a hollow rectangular cathode and a mesh anode in a vacuum chamber, the dimensions of which significantly exceed the discharge geometric aperture. The measurements have been carried out using a combined optical-electrical probe along the discharge central axis both between the electrodes and in the post-anode plasma. For various plasma-forming gases (He, Ne, Ar, and Xe), spatial distributions of the following parameters were obtained: plasma potential Up, concentrations Ne and medium energy $$\left\langle u \right\rangle $$ of electrons, and the intensities of the luminescence of individual spectral lines. It has been established that for all plasma-forming gases, the region of plasma existence significantly exceeds the region limited by the aperture of the discharge system and a significant concentration of electrons is observed in the region behind the anode.