Global Nonlinear Electromagnetic Simulations of Tokamak Turbulence

The particle-in-cell code ORB5 is a global gyrokinetic turbulence simulation code in tokamak geometry. It has been developed at CRPP, Lausanne, Switzerland, with major contributions from IPP, Garching, Germany, and IPP, Greifswald, Germany, under a long-standing collaboration. The code ORB5 solves the gyrokinetic equations in the whole plasma core, including the magnetic axis. A field-aligned filtering procedure and sophisticated noise-control and heating operators allow for accurate simulations. Recently, the code ORB5 has been extended to include self-consistent perpendicular magnetic field perturbations. The inclusion of magnetic perturbations allows for a comprehensive study of finite β effects on microinstability. In this paper, we present the first linear and nonlinear code results concerning electromagnetic effects on tokamak microinstabilities.