ABSTRACT
The ion and electron temperature profiles, the power flow in the plasma edge and its radiated fraction, and the concentration and penetration depth of neutral hydrogen atoms and of plasma impurities into the scrape-off layer (SOL) are examples of such strongly interlinked quantities. The plasma edge must have the appropriate architecture in order to obtain a thermonuclear fusion plasma with high performance. The edge plasma itself is strongly influenced by the plasma-wall interaction. Atoms and ions from the plasma have a strong interaction with matter. A well-known example is the flux of high-energy neutral particles created by charge exchange processes between the energetic protons and the neutral atoms surrounding the plasma, at least for limiter configurations. Regular machine operation of a fusion device is devoted to the generation of a fully ionized plasma, with electron temperatures on the order of hundreds to thousands of electron volts.
