Numerical solution of the ray equations for lower hybrid heating in a Tokamak

Ray tracing is used to construct the power deposition profile of Lower Hybrid waves in toroidal geometry. In agreement with previous work we find that the wavevector component parallel to the static magnetic field decreases on the average as the waves penetrate radially into the plasma. This can affect the accessibility of the absorption region. However, detailed analysis of one ray shows that ray tracing becomes inadequate when toroidal effects are really important (small aspect ratio, large rotational transform)