Heat fluxes considerably larger than anticipated appear to be incident
on the lateral protection of the TORE SUPRA ion Cyclotron Range of Fr
equencies (ICRF) antennas. The antenna lateral protection shows overhe
ating for ICRF power levels greater than 2 MW in dipole mode or 1 MW i
n monopole mode. A possible cause for overheating is a DC sheath volta
ge created on the antenna structure by the ICRF.