Improved theory of energy losses in corrugated inner conductor of coaxial gyrotron cavity

The improved theory of Ohmic losses which takes into account effects of a field increase near edges of corrugations is developed for a coaxial gyrotron cavity with a corrugated inner conductor. It is shown that for the ITER relevant TE_34,19 coaxial gyrotron operating at the maximal output power (~2 MW) they do not lead to a notable increase of the total losses in the corrugated inner insert. However they can contribute substantially to the local density of losses near edges of corrugations especially in the shot pulse regimes when contribution of higher axial harmonics to the total field can be substantial.