Low-Density Theta Pinch Experiments

Abstract

Deuterium plasmas, produced by a theta pinch device, with initial pressure of 0.01 Torr, have been studied by means of neutron measurements, photography, magnetic probes, pick‐up loops, spectroscopy, soft x‐ray absorption, and by the introduction of impurity ions. Most of the plasmas were created in the absence of trapped fields. Typical plasma conditions obtained are: n ∼ 10¹⁶ cm⁻³, T_e ∼ 300 eV, neutron rates of 10¹² sec⁻¹ and ion energies of several keV. The plasma shows no growing instabilities if no reversed field is present. There is particle loss through the end mirrors, with low‐energy ions lost preferentially as in classical mirror confinement.