  The effect of small deviations from a Maxwellian equilibrium on turbulent
momentum transport in tokamak plasmas is considered. These non-Maxwellian
features, arising from diamagnetic effects, introduce a strong dependence of
the radial flux of co-current toroidal angular momentum on collisionality: As
the plasma goes from nearly collisionless to weakly collisional, the flux
reverses direction from radially inward to outward. This indicates a
collisionality-dependent transition from peaked to hollow rotation profiles,
consistent with experimental observations of intrinsic rotation.
