Banana regime pressure anisotropy in a bumpy cylinder magnetic field -: art. no. 012509

The pressure anisotropy is calculated for a plasma in a bumpy cylindrical magnetic field in the low collisionality (banana) regime for small magnetic-field modulations (epsilon equivalent to Delta B/2B << 1). Solutions are obtained by integrating the drift-kinetic equation along field lines in steady state. A closure for the local value of the parallel viscous force B center dot del center dot Pi(parallel to) is then calculated and is shown to exceed the flux-surface-averaged parallel viscous force < B center dot del center dot Pi(parallel to)> by a factor of O(1/epsilon). A high-frequency limit (omega >nu) for the pressure anisotropy is also determined and the calculation is then extended to include the full frequency dependence by using an expansion in Cordey eigenfunctions. (c) 2006 American Institute of Physics.