#

Fluid Velocities

The flux-surface functions
and
are directly related to the lowest-order perpendicular
velocities of the various plasma species in the island rest frame. In fact, as is clear from Sections 4.2, 5.2, and 8.2,
where
Here,
,
, and
refer to the components of the perpendicular electron, MHD, and ion
fluid velocities, respectively. Note that , , and are all zero inside the magnetic separatrix of the island chain.