On the vertical uniformity of an ITER-like large beam

Achievement of the ITER NBI ion source parameters for hydrogen at the test facility ELISE and present Status for deuterium

“…Taking into account additionally the second electrostatic lens formed between the EG and the GG, the divergence for a defined perveance depends also on the voltage ratio for the two gaps, U acc /U ex . The optimum ratio of these voltages is found to be between 5 and 6, both in experiments and calculations [16]. It is assumed that the beamlets are space-charge compensated within a few centimeters behind the grid system such that the divergence increases no longer.…”

“…Details of the positions and capabilities of the different beam diagnostics together with some recent results are given in Ref. [16]. It should be noted that due to beam inhomogeneities and the zig-zag pattern of the negative ions, the line-of-sight averaged divergences resulting from the overlap of several beamlets are typically higher than the one predicted for a single beamlet (see discussion in Sec.…”

Langmuir-probe measurement through the plasma grid aperture of hydrogen negative ion source

“…A negative hydrogen-ion-based Neutral Beam Injector (N-NBI) is a powerful heating and current drive device for future tokamak-based fusion reactors such as ITER and DEMO [1][2][3]. The N-NBI can provide a toroidal current drive, which is necessary to sustain the tokamak configuration.…”

Evaluation of H-/D- Density Using Langmuir Probe Measurement in a Cs Seeded Negative Ion Source

“…Neutral Beam (NB) Injection is a strong candidate for the current drive and heating scheme in future tokamak-based fusion reactors such as ITER and JA-DEMO [1,2,3]. The current drive by NB injection is robust and can be applied at the density range of reactor-relevant plasmas if its injection energy is sufficiently high.…”