Plasma transport across magnetic field lines plays a key role not only in hot fusion plasmas but also in low-temperature plasma sources operating at low pressure, which often rely on external magnetic fields for their operation. Transport in these sources involves different physics than that in fusion plasmas: the ions are not (completely) magnetized, the plasma is sensitive to wall effects because the magnetic field lines intercept the chamber walls, and the neutral gas density is often much larger than the plasma density. This paper gives an overview of the main principles of magnetized low-temperature plasma transport as they are currently understood, including recent insights on the role of magnetic drift. Three important forms of magnetized low-temperature plasma transport are discussed: magnetized plasma diffusion, transport in E × B fields and magnetic drift. These phenomena are illustrated with recent numerical modeling results on a dipolar microwave source, an End-Hall ion source, and simplified version of the ITER negative ion source. For the latter source it is shown that obstructed magnetic drift can lead to plasma asymmetry and increased cross-field transport.

The plasma propulsion with electronegative gases (PEGASES) thruster is a gridded ion thruster that accelerates alternately positively and negatively charged ions to provide thrust. Over the last few years, various prototypes have been tested, adequate diagnostics have been developed, and analytical models and simulations are made to better understand and control the physics involved. Here, we present the state-of-the-art in the PEGASES development as of 2013, and discuss its possible future in space.Index Terms-Electric propulsion, electronegative plasmas, ion-ion plasmas, negative ion thrusters.