Launcher heat load on high power LHCD experiments in JT-60U

Naito, Osamu; Ikeda, Yoshitaka; Seki, Masami; Ide, Shunsuke; Kondoh, Takashi; Ushigusa, Kenkichi

Heat loads on a lower hybrid wave launcher as well as on the first wall during high power auxiliary heating and their origin are investigated. It is found that the heat load on the launcher is moderate during injection of lower hybrid wave into a ohmic plasma. However, it is significantly enhanced by the existence of high energy banana-trapped particles and localized near the equatorial plane. In JT-60U, lower hybrid wave can be coupled to the plasma at a launcher-plasma distance of ~ 20 cm without any significant heat load on the launcher grill. Nevertheless, the heat load due to banana-orbit particles may impose a constraint on the position of a launcher.