Magnetic momentum probe for plasma studies with application to high pressure plasmas

Summary form only given. A magnetic momentum probe¹ is investigated. This diagnostic device appears similar to a Langmuir probe, but interacts with particles by magnetic field rather than (or in addition to) an electric field. The probe is a bare wire loop immersed in the plasma. When a DC current flows through the wire, it is surrounded by a magnetic field which diverts charged particles. In this way, the momentum of plasma particles can be measured. The Langmuir probe in contrast measures particle energy.The Langmuir probe has the disadvantage of not working well at high pressure because of the high density of electrically charged particles. A magnetic field penetrates through the charged particles to allow interaction with particles farther from the probe. The magnetic field also suppresses secondary electron emission from the probe. The momentum probe allows a mass analysis of the various ionic species in the plasma. An electrostatic potential has been introduced to the magnetic momentum probe to add some of the characteristics of a Langmuir probe.