Turbulence suppression by shear in the E×B flow is a widelyaccepted mechanism. Edge polarization experiments on TEXTOR-94 have beenused to study the dependence on the toroidal magnetic field, plasma currentand plasma composition of the critical E×B shear, definedas the highest rate of change in the diffusion coefficient with shear. Ourexperiments show that an increase of the isotopic mass and/or a decrease ofthe toroidal magnetic field leads to higher critical E×Bflow shear, whereas a change of the plasma current seems to have no effect.
Sheared flow generation and mode suppression in a magnetized linear cylindrical plasma