Magnetic Nozzle Radiofrequency Plasma Systems for Space Propulsion, Industry, and Fusion Plasmas*)

Low-pressure radiofrequency (rf) plasma sources have been widely used in various fields. When static magnetic fields are applied to these sources, a diverging magnetic field configuration known as a magnetic nozzle forms downstream of the source and interesting phenomena are observed. Such structures are frequently observed in space, e.g., the surface of the Sun and the geomagnetic fields. Here, the studies performed by the authors over the last decade on the fundamental plasma physics, the space plasma propulsion, the industrial plasma technology, and the radiofrequency ion source, are briefly overviewed. The design of sources based on the type of application is an important issue. Integrating a rf plasma source into a system often requires a compact and automatically controlled system, as presented here. Herein, interaction between the low-temperature plasmas and the hot fusion plasmas is sometimes mentioned in terms of "Plasma Apparatus."