In thermonuclear fusion plasmas, transport losses are usually believed to becaused by turbulent fluctuations. Particularly in the outer region oftokamaks, stellarators and reversed field pinches, electrostatic turbulenceaccounts for particle transport. In tokamaks, electrostatic fluctuations canalso be responsible for the radial energy flux; in reversed field pinches,energy transport cannot be ascribed to electrostatic turbulence only.In the plasma edge of the reversed field experiment device, identified as the region between thetoroidal field reversal and the first wall, an extensive study of magneticfluctuations and of the related radial energy flux has been performed. It isfound that magnetic fluctuations carry most of the radial flux of energy.However, close to the wall the magnetic fluctuation-driven energy fluxdecreases abruptly, so that another mechanism must be invoked. There areindications that the energy flux channel in this region is the macroscopicmagnetic deformation due to the phase locking of magnetic modes.
Plasma flux motion in a toroidal plasma guide