Development of a translation stage for beam studies in the negative ion source SPIDER

Beam diagnostics play a crucial role in characterizing the beam performances of SPIDER, the prototype negative ion source for the ITER neutral beam injection system. To enhance the alignment and spatial resolution of Beam Emission Spectroscopy (BES) diagnostics, a remotely controlled translation stage capable of sub-millimeter accuracy has been developed. This stage allows dynamic adjustments of lines-of-sight (LOS) to improve alignment with individual beamlets and enable detailed scans of the beam for homogeneity and divergence studies. Preliminary tests demonstrate the system’s ability to measure beam divergence and intensity variations with high precision, validating its potential for optimizing beam performance. Future applications include advanced studies of single beamlet divergence, validation of emission codes, and support for MITICA diagnostics.