Experimental Observations of Steep Temperature Steps in Dense Magnetized Plasmas

Quasi-steady-state steep temperature steps have been experimentally observed in dense (>10¹⁹m^-3) linear magnetized helium plasma columns submerged in a high-density ( $>100$ mT) neutral-gas environment. The formation of such features is found to be favored by a high neutral gas density or a positive bias (≥Vfl) placed on the end plate. A rapid reduction in plasma density and electron temperature is observed to exist across the steps, as is a dramatic increase in neutral line radiation. Potential steps are inferred. Detailed Langmuir probe measurements have revealed three-dimensional structures. Possible mechanisms of formation are discussed.