PLASMA SIMULATION OF A LANGMUIR PROBE WITH NORMAL MAGNETIC-FIELD

The response of a probe with varying applied potential is studied by numerical simulation. Each particle is followed in turn in its path through the test volume and leaves a space charge in its track for the next overall iteration. The space charge is inversely proportional to its local speed [L.W. Parker and E.C. Whipple, Ann. Phys. 44 (1967) 126]. Preliminary results indicate that the effects of a magnetic field is strong and consistent with an anomalous diffusion, indicating that we may be simulating some process in real plasmas, in spite of the fact that the simulation method employed in principle gives no information on the temporal development of the plasma. On the other hand, effects of collisions seem to be slight.