Heating at the Electron Cyclotron Frequency in the ISX-<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>B</mml:mi></mml:math>Tokamak

Results are reported of electron-cyclotron-heating experiments in which 80 kW of microwave power from a 35-GHz gyrotron is injected into a tokamak with large single-pass absorption. For 10-ms microwave pulses, incident from the high-field side of the torus, the central electron temperature increases from 850 to 1250 eV, in agreement with empirical transport-code calculations. For the first time it is demonstrated that electron temperature in a tokamak scales linearly with electron-cyclotron-heating power.