Ion Temperature Distribution in Current Sheets Formed in Argon Plasma

Abstract

The processes of heating and acceleration of argon ions in different charge states in current sheets formed in 2D and 3D magnetic configurations were studied experimentally. It is shown that the temperature of argon ions depends on the ion charge state. The maximum temperatures of Ar II, Ar III, and Ar IV ions are found to be 60, 120, and 200 eV, respectively. The time of energy exchange between ions due to Coulomb collisions is much shorter than the current sheet lifetime, which indicates that ions in different charge states reside in different sheet regions located at different distances from the sheet midplane (y = 0). It is shown that Ar II and Ar III ions are accelerated to energies of $$W_{x}^{{\max }}$$ ≈ 200 eV. It is found that the temperature and the energy of directed motion of Ar II, Ar III, and Ar IV ions do not depend on the magnitude of the longitudinal magnetic field. Argon ions Ar IV radiating in the near UV region are detected for the first time in the current sheet plasma.