Lower hybrid wave (LHW)-plasma coupling and lower hybrid current drive (LHCD)experiments in divertor, including single-null and double-null, and limiter configurations wereconducted systematically in EAST. A maximum power for launched LHW is 1.4 MW and theplasma current with LHCD is about 1 MA. It is indicated that the coupling is best in limiterconfiguration, then in single-null one, while worst in double-null one. Study in current driveefficiency by a least squares fit shows that there is no obvious difference in drive efficiency betweenthe double-null and the single-null cases, whereas the efficiency is a slightly lower in the limitercase. The effect of plasma density on the current drive efficiency is due to the influence of densityon impurity concentration.
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