The enhancements of the residual Reynolds stresses and symmetry breaking with resonant magnetic perturbations (RMPs) are presented. These experiments were performed using a Langmuir probe array in the edge plasmas of the J-TEXT tokamak. This study aims at understanding the generating mechanisms of residual stresses and intrinsic rotations. It is observed that, with RMPs, the peaked residual stresses, steeper pressure gradients and stronger shear layers all appear around the resonant surface. The toroidal rotation is accelerated in the direction of the

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The toroidal component of the velocity for geodesic acoustic modes (GAMs) is first demonstrated. Multiple Langmuir probe arrays set up near the top tokamak of the J-TEXT were utilized for this study. A significant peak at the GAM frequency is observed in Mach number fluctuations. The toroidal velocity for the GAMs is estimated as∼10-100 m s −1 and increases with the poloidal velocity. The ratio of toroidal component to the poloidal one of the velocity is mainly located in the interval between 0.3 and 1.0. With higher safety factors q, the ratio almost does not change with decreasing the safety factor, whereas it goes up sharply at low q. The coherencies between poloidal electric fields and Mach number fluctuations in turbulence frequency bands are also evaluated, and are higher than those between radial electric fields and Mach number fluctuations.