Neutral current sheets in laboratory and space plasmas

Formation of a neutral current sheet in a plasma with a strong magnetic field containing a zero line is considered, and the nature and stability of the sheet are discussed. Investigation of solar chromospheric discharges wherein large quantities of magnetic energy were transformed into the energy of charged particles led to research into developing plasma accelerators that cause energy to accumulate slowly in the vicinity of a current sheet and then to be rapidly released in such a way that a substantial portion of this energy is converted into the kinetic energy of accelerated particles. Characteristic values of temperature, plasma density and magnetic field intensity in space and laboratory plasmas being closely related, the ordered relationships between these phenomena were investigated. A quasi-stationary neutral sheet was produced by applying a homogeneous electric field along the axes of a magnetic quadrupole; the sheet was subsequently broken up by electric field impulses. Ion-acoustic disturbances, due either to heating the plasma or escape of charged particles, appeared in the sheet. Problems encountered in analyzing the sheet are discussed.-