Generation of large-volume plasma by making use of multi-needle plasma at low-pressure

The description and investigation of a large-volume plasma source at low pressure are presented in this article. This new system is a modification of large-volume plasma source operated by thermionic filaments, and is an application of multi-needle plasma at atmospheric pressure stabilized by the flowing channel of a working gas through a high-voltage electrode operated by a AC (20 kHz) power supply. The weakly magnetized plasma is created by direct ionization of the background gas by low-energy electrons generated from multi-needle plasma, which are annularly arranged at one end of a cylindrical chamber. The bulk plasma experiment is conducted in the cylindrical stainless steel chamber with a radius of 0.5 m and a length of 3 m. Also, presented are preliminary experimental results of multi-needle plasma at atmospheric pressure.