Experimental and theoretical studies of the STP-3(M) reversed field pinch in the high current density regime

Reversed field pinch experiments are carried out, with a high current density of up to 7 MA·m-2. The electron temperature is nearly proportional to the current density. The self-organizing action and its effect on plasma confinement are investigated experimentally and theoretically. The typical RFP behaviour is essentially the same in the entire current density region of 2 to 7 MA·m-2. In the high current density regime, the magnetic fluctuation level decreases slightly and plasma-wall interaction caused by the dynamo action sets in. (author)