The ITER ECH heating and current drive system consists of 24MW at 170GHz, which can be directed to either the equatorial or upper port launching antennas (launchers) depending on the desired physics application. The upper launcher reference design [1,2] (UL), see figure 1a, uses a front steering (FS) mirror  that sweeps the beam in a poloidal plane providing co-ECCD over the range of 0.64≤ρψ≤0.93. The launcher has a single dedicated purpose of stabilising the neoclassical tearing modes (NTM), with the launcher steering range accessing the region in which the q=3/2 or 2 flux surfaces are expected to be found for scenarios susceptible to NTM  , see figure 1b. The FS launcher focuses the RF beam to a small spot size near the resonance surface, with the deposition width (wCD) the order of marginal island width (wmarg) and the maximum current density (jCD) exceeding the local bootstrap current density (jBS). The performance of the FS launcher far exceeds (by a factor of 1.5 to 3)  that required by the physics to stabilize the NTM, where the NTM stabilization figure of merit (defined as ηNTM=jCD/jBS��) should be �ηNTM≥1.2 for complete NTM stabilisation . a) b
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