understanding the plasma potential as a confinement method

In a multi-dipole DC hot filament argon discharge, a transition from positive to negative plasma potentials were examined. A new confinement method in negative plasma potential were obtained Emissive probes, Langmuir probes, ion acoustic waves and laser induced fluorescence were employed in order to measure the plasma parameters. Potential dips and wells and also ion sheaths, electron sheaths were obtained and investigated theoretically and experimentally. It is found that primary electron energy plays important role in plasma potential. Experimental results and theory will be discussed.