Anomalous Diffusion of a Plasma across a Magnetic Field

The diffusion of a plasma across a magnetic field is considered both theoretically and experimentally. It was found out that the fluctuation of the density can cause an anomalous diffusion that is inversely proportional to the magnetic field B. The mobility of electrons perpendicular to the magnetic field was measured in the experiment; the measurement supports 1/B diffusion. The density fluctuation was also measured. There is good agreement between the observed mobility and the theoretical one derived from the density fluctuation. The potential fluctuation was found to be an increasing function of the external potential and independent of the magnetic field intensity. This fact also indicates that fluctuation or turbulence plays an important role in the anomalous diffusion.