Gyrokinetic Simulation of Tokamak Edge Plasmas

It has been recently discovered that the trapped electron mode (TEM) may play an important role in the H mode edge plasma for domestic tokamaks such as EAST and HL-2A. The stability and transport for TEM for the edge parameters are studied using large scale gyrokinetic particle simulations. The gyrokinetic simulation reveals the parametric dependences on the wavelength and collisionality. The ballooning mode structure of this instability is found un-conventional with peaking at up and down side of the poloidal plane for the steep gradient H mode edge. The frequency stair case is found for the linear dispersion, which can be understood as a jump between different branches of the linear eigenmode.