A global gyrokinetic toroidal particle code for a 3D nonlinear simulation (GT3D) [1] has been developed for a comprehensive study of the ion and electron anomalous transport arising from the ion temperature gradient driven - trapped electron mode (ITG-TEM) turbulence in reactor relevant tokamak parameters. In GT3D, gyrokinetic ions and drift-kinetic electrons are solved using a finite-element PIC method [2]. The code uses a new δf method based on a canonical Maxwellian distribution F_CM(P_φ,ε,μ), which is defined by three constants of motion in the axisymmetric toroidal system, the canonical angular momentum P_φ, the energy ε, and the magnetic moment μ. Through zonal flow damping tests, it is shown that the method is essential for simulating a correct zonal flow response. A quasi-ballooning field solver enables linear and nonlinear high-m,n global calculations with a good numerical convergence. Conservation properties are improved by using the optimized particle loading [3]. The code has been optimized for massively parallel scalar and vector machines, and it operates with high processing efficiency and scalability on the JAERI Origin3800 system and on the Earth Simulator.
In the linear ITG-TEM calculations, basic properties of ITG-TEM modes are confirmed. Adding trapped electrons not only increases the growth rate of the ITG mode, but also produces another unstable electron mode, the TEM mode, which is unstable even at η_i∼0. The dominant mode changes from the ITG mode to the TEM mode depending on k_θ and η_i. In linear benchmark calculations using Cyclone base case parameters [4], eigenfrequencies obtained from GT3D, GTC and FULL show reasonable quantitative agreement [5].
Recently, an annular torus version of GT3D has been developed to study the electron temperature gradient driven (ETG) turbulence, which is considered as another candidate for the electron anomalous transport. In the talk, preliminary ETG calculations will be shown.

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