Role of electric field curvature in the formation of edge transport barrier

In this study, the roles of non-uniformity E-r (i.e its shear plus curvature) effects on the edge transport harrier formation are experimentally investigated, we have identified the mechanisms centered around the role of the E-r-curvature on the edge transport harrier (ETB) formation. In addition, we recognized a new role of the E-r-shear as for the expansion of pedestal width, compensating an unfavorable effect of the E-r-curvature having its sign dependence on the turbulence transport.