Power flow from a plasma having complex electroacoustic-wave impedance

The complex electroacoustic-wave impedance is examined and is related to power coupling at a plasma-vacuum boundary via the planewave solution of Maxwell´s equations. The reactive component of impedance, which is due to the inclusion of a nonzero collision frequency, is found to be important at frequencies less than the plasma frequency, where it contributes a significant amount to power flow. Thus, at those frequencies, serious errors can be introduced by assuming that the electroacoustic power is made up of the powers in the incident and reflected waves only.