At present, FTU at the Centro Ricerche Energia (Association EURATOM-ENEA) in Frascati is the only high magnetic toroidal field tokamak operating in Europe (up to 8 Tesla, 1.6 MA) extending the database on confinement and heating necessary for ITER to high magnetic field and high-density regimes.

The FTU (Frascati Tokamak Upgrade) 8 GHz LHCD system has recently been operated close to its design value. This means: 6 gyrotrons feeding 6 independent wave guides launchers with a total launched power of 2.4 MW (about 4.4 MW at source) for 0.5 sec. At this power level, current drive experiments can be performed in conditions similar to the one foreseen for ITER advanced steady state scenarios. In effect, the LHCD system has been operated up to 2.2 MW for a time durationlasting several times the energy confinement time (typically 10 times) at density and magnetic field high enough to be relevant for ITER.

A substantial increase of the neutron yield, typically by a factor of five, is observed. This indicates that a good collisional transfer between the bulk ions of the plasma and the Lower Hybrid accelerated fast electrons is taking place.

Off-axis LHCD has also been used to produce electron internal transport barriers (ITB) at relatively high densities. ITBs are sought to be an important feature of the advanced scenarios foreseen for ITER allowing steady state operation to be achieved. By broadening the plasma current profile with off-axis ECRH (Electron Cyclotron Resonance Heating) during the plasma current ramp-up phase, ITBs were subsequently produced with 1.7 MW of LHCD leading to high central temperature for several energy confinement times.

Further development is taking place, in particular in combining ECRH (140 GHz) and LHCD systems at the highest possible densities in order to prepare ITER advanced scenarios.

The Lower Hybrid Current Drive is a non-inductive current drive using lower hybrid waves. The Lower Hybrid range of frequencies is 1- 8 GHz and it is between the one of the Electron Cyclotron Resonance Heating and the one of the Ion Cyclotron Resonance Heating.

Electron Cyclotron Resonance Heating uses radio-frequency waves resonating with electrons gyrating in the magnetic field, corresponding to frequencies in the range of 30 to 170 GHz.

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