Lower hybrid current drive experiments on JETFunded under: FP2-FUSION 10C
The new JET Lower Hybrid Current Drive (LHCD) system has been operational during the 1990 experimental campaign; up to 1.6 MW at 3.7 GHz have been coupled to 2 and 3 MA plasmas in the limiter and X-point configurations. 20 sec long LH pulses have led to steady state plasma conditions with a 50% drop in the loop voltage measured up to n bar (e) = 2 x 1.0 E19/m3. The broadening of the current profile is observed to increase with increasing electron density. Combined operation of Ion Cyclotron Resonance Heating (ICRH) and LHCD has resulted in current drive efficiencies gamma = n bar (e)I(CD)R/P(LH) with a value of approximately 0.4 x 1.0 E20/m2 A/W at volume averaged electron temperatures of 1.9 keV and stabilisation of sawteeth up to 2.9 sec. LHCD operation is associated with central electron heating at about 1 keV/MW at n bar (e) values of about 1.8 x 1.0 E19/m3, while generating a hollow shell of suprathermal electrons, as measured by a newly installed Fast Electron Bremsstrahlung diagnostic.
Bibliographic Reference: Report: JET-P(91)45 EN (1991) 45 pp.
Availability: Available from the Publications Officer, JET Joint Undertaking, Abingdon, Oxon. OX14 3EA (GB)
Record Number: 199210162 / Last updated on: 1994-12-02
Original language: en
Available languages: en