Radiation losses from oxygen and iron impurities in a high-temperature plasma

Publisher Website
Google Scholar
Abstract
Radiation and ionization losses due to impurities present in a high-temperature plasma have been calculated for a light element (oxygen), which is completely stripped in the core of existing tokamak discharges, and a heavy one (iron), which is only partially stripped. Two extreme cases have been treated: a) corona equilibrium is attained; the radiated power is then equal to the product of electron density ne, impurity density nimp, and a function of the electron temperature, Te; b) impurities re-cycle with a constant radial velocity v0 (either inwards or outwards) in a background plasma (represented by the radial profiles of ne and Te). In this case, radiation and ionization losses are proportional to the impurity flux ψimp and are a decreasing function of the diffusion velocity v0. The results presented can be used to evaluate losses in a practical case.