Dielectric losses in gases under ionizing radiation

In future fusion reactors as well as in machines, such as ITER or NET, there will be a new dimension when compared with actual machines, and that is the presence of a high radiation field, both ionizing and displacement. This requires the design and development of radiation resistant systems which may be operated under radiation. In the case of heating systems the measurements of radio frequency window materials has been started only recently to be performed under radiation. These measurements should be made with special attention due to the perturbation induced by the ionization of the filling gases. This effect could also be important in high power heating systems based in pressurized waveguides due to the presence of ionizing radiation. Here the radiation effects on the dielectric properties of different gases at atmospheric pressure are presented. The gases investigated are air, helium, nitrogen, argon, carbon dioxide, and SF6