Classical diffusion
The classical diffusion of plasma confined by the magnetic field refers to the collision dominated transport that follows the 1/B scaling, where B is the magnetic field strength.
Diffusion is a random walk process that can be quantified by the two key parameters: Δx, the step size, and Δt, the time interval when the walker takes a different step. Thus, the diffusion coefficient is defined as D≡(Δx)/(Δt).