Orbit-averaged Guiding-center Fokker-Planck Operator

A general orbit-averaged guiding-center Fokker-Planck operator suitable for the numerical analysis of transport processes in axisymmetric magnetized plasmas is presented. The orbit-averaged guiding-center operator describes transport processes in a three-dimensional guiding-center invariant space: the orbit-averaged magnetic-flux invariant $\ov{\psi}$, the minimum-B pitch-angle coordinate $\xi_{0}$, and the momentum magnitude $p$.