Test Particle Transport due to Long Range Interactions

Enhanced cross-field transport of test particles is observed in a quiescent, steady-state pure ion plasma. The measured particle diffusion is about ten times faster than predicted by classical collisional theory over a wide range of densities, temperatures, and magnetic fields, whereas the measured velocity-space isotropization agrees closely with collisional theory. This enhanced diffusion scales essentially as $B^{-2\mathrm{}}$ and is probably due to long-range “ $\mathbf{E}\times \mathbf{B}$ drift” collisions, with interaction distances $\rho$ in the range $r_c<\rho <{\lambda }_D$.