Electron heated internal transport barriers in JET

By applying lower hybrid current drive (LHCD) for strong electron heating and off-axis current drive starting very early in the discharge, an electron internal transport barrier (eITB) can be generated. The barrier is formed just inside the location of minimum q, and slowly moves inward with this location. During the current flat-top the barrier can be sustained during many seconds, either with continued LHCD, or by ion cyclotron resonance heating. In this paper both scenarios are analysed and compared.

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