Numerical simulation of plasma processes occurring in the ram region of the tethered satellite

Plasma processes affecting collection of electrons by a conducting body in a magnetized plasma are studied using a fully 3-dimensional particle-in-cell simulation, including a relative drift (Vo) between the plasma and the body. The main focus of the paper is on the plasma processes occurring in the ram region when the body potential Φo > Wo /e where Wo is the ram energy of the ions in the rest frame of the body. The potential structure near the body and the resulting flow of electrons and ions are critically examined to determine the sources of free energy for exciting plasma waves, which can possibly accelerate electrons to superthermal energies. Simulations reveal that the E × Bo drift of the electrons in the body's sheath, shifted toward the ram region and extended along the magnetic field Bo, produces sufficiently large relative drifts between the electrons and ions across Bo to excite lower hybrid waves. It is estimated that such drifts in the sheath of the tethered satellite was able to produce lower hybrid waves which could accelerate the electrons up to a few hundred electron volts.