ENERGY DYNAMICS IN LINEAR MHD WITH ION PARALLEL VISCOSITY

Analytic results fur the time dependences of the kinetic and magnetic energies of an incompressible magnetofluid threaded by a strong unifor m magnetic field B-0 are obtained. The governing equations are tile li nearised magnetohydrodynamic (MHD) ones, but with the conventional Lap lacian dissipation replaced by ion par allel viscous effects. The beha viour is shown to depend on the relative sizes of the Alfven frequency and the viscous and resistive dissipation rates, For many cases equip artition of the kinetic and magnetic energy holds at tile (Fourier) mo dal level. An important exception to this behaviour occurs for two-dim ensional fluctuations? that is when the wavevectors are perpendicular to B-0.