The gas puff imaging diagnostic is used for the investigation of the poloidal flow and turbulent fluctuations at the plasma edge and scrape-off layer (SOL) on the HL-2A tokamak. The impact of resonant magnetic perturbations (RMPs) on the edge poloidal velocity ( ${V_\theta }$ ) are investigated and compared during the operation of a stair-like rising RMP coil current ( ${I_{{\text{RMP... https://www.hindigyanvishv.com/