The bootstrap current produced by fusion born alpha particles is obtained retaining effects of slowing down drag, pitch angle scattering, and arbitrary aspect ratio. The result is presented both as a summation of a rapidly converging series and a simple Pade approximation good for arbitrary aspect ratio. Quantitative results are derived using International Thermonuclear Experimental Reactor (IT...

In this paper we present two different, heuristic error estimates for the Pade-type approximation of transfer functions via an Arnoldi algorithm. We first suggest a convergence criterion between two successive reduced models of the order and . We further propose to use the solution of the Lyapunov equations for reduced-order systems as a stop-criterion during iterative model order reduction.