Design and fabrication of the “ITER-like” SINGAP D− acceleration system

To demonstrate ITER NBI (1 MV, 40 A) relevant beam optics in the Cadarache 1 MV, 100 mA test bed, a new D− beam source system has been put into operation. The system retains a maximum of the ITER SINGAP key parameters, e.g. the perveance matched D− current density at 1 MeV is 20 mA/cm2. The accelerator parameters are identical to the ITER SINGAP design, aiming at a near parallel 1 MeV beam of 5 mrad divergence. The design is aimed at also demonstrating SINGAP “on to off-axis” beam steering by a simple transverse displacement of the post-acceleration electrode. First beams up to 850 keV have been obtained after only 4 weeks of commissioning.