Experimental Studies of Plasma Confined in a Toroidal Heliac

Abstract

The design, construction and operation of the prototype heliac SHEILA are described. Gas breakdown conditions are compared with high frequency discharges. Plasma isobars obtained from local measurements are shown to agree closely with computed magnetic flux surfaces for a range of magnetic configurations. The effect of changing the configuration on fluctuation mode numbers is demonstrated and shown to be consistent with the calculated rotational transforms.