Carbon radiation in the vicinity to the neutralisation plates

As known, the reradiation of energy in the divertor volume is one of the possible ways of reducing the specific heat loading to the divertor plates of the ITER reactor. The existing calculations of radiating power from a plasma with various impurities show, that the radiating power turns out to be insufficient for the complete reradiation of energy flux entering a divertor at the plasma parameters characteristic for the divertor zone, although the radiation loss power rises with a reduction in the electron temperature. One should note, that practically all the calculations of radiating power loss are done in the corona approximation, when it is considered that the main role in the balance equation for ions of various multiplicity, as well as that in the balance equation of population levels, is played by atomic processes, the space and time effects are neglected. However, in the zone nearly the divertor plates the situation can be changed, since the escape of charged particles to the divertor plates and the emergence of neutral atoms from them play an important role. In this case, noticeable deviations from the corona model are possible that, in its turn, can result in a change in the calculated power reradiated in the divertor channel. (author) 4 refs., 2 figs