ECH Launching Gonditions in Helical System

Launching conditions for electron cyclotron heating (ECH) are studied on Heliotron E. In heliotronltorsatron configurations, the polarization of the launched wave should be determined by taking into account the effect of magnetic shear. The best-localized heating is obtained when the electric field of the launched wave is off-normal to the resonant magnetic field even for perpendicular beam injection. The experimental results are in good agreement with the numerical calculation results including the magnetic shear terms.