Magnetically Tailored Arc and Glow Discharge Plasmas for Atomic Spectroscopy

Abstract

Three magnetic field-plasma configurations are used to study the interaction of external magnetic fields with analytically useful plasma devices. First, a magnetic field oscillating at 60 Hz and normal to the electric field in a 12-A direct current arc plasma is used to obtain an Ē×B̄ drift motion of the arc current channel. This causes a periodic vertical displacement of the channel. Second, a cw magnetic field is used to alter the structure and radiative properties of a demountable glow discharge lamp that uses a center-post cathode. The magnetic field axis is parallel to the cathode axis, and the lamp is operated in a pseudo-magnetron mode. Third, a damped, oscillatory magnetic field produced by discharging a capacitor through a coil is used to alter the radiative characteristics of several commercial hollow cathode lamps. The magnetic field is parallel to the cathode axis, and again the lamps operate in a pseudo-magnetron mode. In all three systems, the presence of the magnetic field drastically alters the radiative properties of the plasmas.