Development of a compact microbeam system

Abstract We have developed the MB-I and MB-II lines, consisting of quadrupole lenses, object and divergence-defining slits, and integration with IBA techniques for application in multiple fields. The general-purpose type of MB-II, MB-II-AQUA has been used not only at Tohoku University but also in other laboratories. However, the total beamline length is substantial due to the doublet configuration, limiting its introduction in certain laboratory environments. To address this issue, we considered shortening the beamline by implementing a triplet configuration and investigated the impact of shortening the existing MB-II line. Our findings indicate that, even with a reduced object–lens distance, a beam size of approximately 1 μm can be achieved. However, to achieve a beam size smaller than this, the divergence angle must be narrowed. In such cases, doublet configurations proved more advantageous because the effect of spherical aberration was minimized. The performance of the triplet system may vary depending on the laboratory; it is greatly influenced by the brightness distribution of the accelerator. In any case, the triplet system can be easily switched between the doublet and triplet arrangements through wiring and can be adapted for different purposes. As such, the compact MB-II-AQUA-SH microbeam system provides considerable flexibility for various fields and applications.