Diffusion And Topological Properties Of Phase Space In The Standard Map in the Tokamak
institut de formation technique
Last modified: May 16, 2006
In this work, we have interested to the statistical properties of chaotic field lines in the toroidal geometry of the Tokamak. The poincaré representation of magnetic field lines and the corresponding diffusion coefficient in the presence of resonances are derived. What follow, a particle diffusion process through the island chains in the presence of a weak stochastic perturbation and we show how to modify the methods described in [1,7]. We will include the presence of the stochastic perturbation by including in the standard mapping the effect of the random jump x in the phase variable. The normalised diffusion coefficient computed analytically and compared with numerical computations.