VARIATIONAL STRUCTURE FOR DISSIPATIONLESS LINEAR DRIFT-WAVE EQUATIONS

A derivation from first principles of the Lagrangian density for the d issipationless linear drift-wave equation recently introduced by Matto r and Diamond [Phys. Plasmas 1, 4002 (1994)] is presented. An exact wa ve-action conservation law for linear drift waves propagating in a rot ating magnetized plasma is then derived from the Lagrangian density wi thout requiring the use of the eikonal representation for the wave fie lds. (C) 1996 American Institute of Physics.