On the thermodynamics of diamagnetic plasma expansions

Summary form only given. Particle-in-cell simulations of diamagnetic plasma expansions were used to illustrate the interplay of energy among the ions, electrons, background magnetic field, and generated electrostatic and electromagnetic waves. As the expansion proceeds, the field lines bend to accommodate the expanding plasma, and magnetic mirrors, or necks, form at the axial expansion fronts. At the expansion necks, all species lose energy more slowly than the adiabatic. The electrons are isothermal throughout the plasma and remain hotter than the ions. Meanwhile, low pitch-angle ions leave the simulation box, reducing the ion temperature anisotropy. The expansion slows when the energy density of the expanding plasma falls below that of the external field. Eventually, the field collapses back upon the plasma heating it