Simulation, code benchmarking and optimization of the magnetic field configuration in a Negative Ion Accelerator

SPIDER is a full-size Negative Ion Source and a multi-beamlet 100 kV accelerator, presently under construction in Padova and is part of PRIMA, the test bed for the full development of the Heating Neutral Beam system for ITER. During the final design, the SPIDER extractor and accelerator system has been improved with respect to the original configuration. In particular, the magnetic configuration has been optimized in order to improve the performances in terms of ion beam optics and aiming, and to obtain an efficient filter for the extracted electrons.