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A particle algorithm for linear kinetic analysis in tokamak plasmas is developed. Linear kinetic stability of a tokamak plasma is analyzed as an initial value problem. Particles are used to sample plasma elements along equilibrium characteristics in 4-dimensional phase space (R,z,v?, ?). Each particle is accompanied with a weight which is a function of the toroidal angle. Integrals in the phase space are evaluated through the weight function and the particle location in the 4-dimensional space. Destabilization of ann=2 toroidal Alfven eigenmode is investigated as a test of the algorithm, and convergence in number of used particles is assessed.

We have developed an electrostatic macro-scale implicit particle simulation code which enables us to simulate low-frequency plasma wave phenomena with large spatial scale length. Specifically, the Poisson equation with the implicit susceptibility term is accurately solved in our scheme with the “strict differencing” and “the consistent filtering.” Linear properties of the simulation scheme, such as the linear stability and the dispersion relation, are examined. We have also applied our simulation code to the excitation and nonlinear saturation of the ion temperature gradient (ITG) drift instability in a system with a shearless slab geometry. The linear properties of the excited ITG mode are compared with the theoretical prediction to find a good agreement.