Probe measurements of electron distribution function in a large-volume glow discharge device with coaxial gridded hollow electrodes.

In this study the electron distribution function (EDF) in a weakly ionized plasma of a large-volume glow discharge device with coaxial gridded hollow electrodes has been measured with a single electric probe. The diameter and the length of the discharge chamber are 50 cm and 40 cm, respectively. The discharge is created by an ac power supply with a frequency of 20 kHz and a maximum power of 2,000 W, which can be varied from 500 W and up. Because of the bipolar diffusion, charged particles are generated between the two poles and spread rapidly to the central region of the discharge chamber, thus forming a homogeneous plasma. The discharge device has been described in details in [1]. The discharge has been created in helium gas at pressure from 40 to 60 Pa. The EDF for different discharge power in the range from 1,200 to 1,600 W and different pressures have been studied. The experimental results have been compared with modeled EDFs. [1] Yuan C., Kudryavtsev A. A., Saifutdinov A. I. et al., IEEE Transactions on Plasma Science, 45, 3110-3113, 2017.