Mass spectrum analyses of Hn+ in the cathode sheath of the pure H2 abnormal glow discharges

The ion species of Hn+ (n = 1-3) and their relative intensities in the cathode sheath of the pure H2 abnormal glow discharges with various H2 gas pressure and different discharge current are analysed with a mass spectrometer. The result shows that the H+ component of ions is dominated, no less than 90 percent, and the H3+ smaller, the H2+ hardly detectable in the H2 pressure range of 133 Pa to 665 Pa. The ratio between H+ and H3+ intensities increases with the gas pressure. The total intensity increases with the discharge current, and the ratio between H+ and H3+ intensities is unchanged. The main physics-chemistry processes in the hydrogen plasma are discussed