Co-counter asymmetry in fast wave heating and current drive

摘要

Different plasma responses to neutral beam injection in the directions co and counter to the plasma current have long been accepted as well understood in neutral heating of tokamak plasma. Differences can also occur in fast wave heating and current drive in the ion cyclotron range of frequencies(ICRF)when antenna arrays are phased to drive current co and counter tot he plasma current. The source of this asymmetry can be easily seen in the code plasma wave equation with an applied magnetic field in the z direction and the parallel ICRF electrical field set to zero(small electron mass limit).