Design and first results of a retractable 1D-CFC beam target for BATMAN upgrade

BATMAN Upgrade (BUG) is a test facility for the production of negative ion beams from an RF driven plasma source devoted to supporting development ITER Neutral Beam Injection (NBI). BUG consists IPP prototype and multi-aperture grid system corresponding roughly beamlet group NBI system, i.e. arrangement 14 (vertical) ×5 (horizontal) Ø14 mm apertures, meaning beam comprised 70 individual beamlets. The can be extracted with up 10 kV accelerated total voltage 45 s (steady state operation underway). One goals detailed study optics. So far, permanently installed diagnostic consisted several lines sight Emission Spectroscopy (BES) at two different positions thermocouple measurements on dump calorimeter. Resolving divergence deflection single beamlets technically exceptionally difficult existing tools, therefore, target made out one-directional carbon fiber composite material (1D-CFC) dimensions 376×142×20 mm³ has been distance 851 exit system. thermal footprints are observed back side via infrared imaging high spatial resolution (<0.7 mm/pixel) that allows characterization low divergence. rotated make it compatible long pulses forthcoming steady operation. safety analysis operational scenarios presented together energy-based interlock. Finally, accuracy estimating shape heat flux front temperature profile assessed, based FEM simulations beamlet.