Preliminary results of microbeam at Tohoku University

A microbeam system is under construction in the Dynamitron laboratory at Tohoku University for the purpose of applying X-rays produced by a microproton beam as monochromatic X-ray point source to biological and materials research etc. The system consists of a dedicated beam line with a doublet quadrupole and a slit-system of microslits, divergence-defining slits and baffle slits connected to the 4.5 MV Dynamitron accelerator's energy analyzing system, which was a newly installed second analyzing magnet. The demagnification factors are 8.0 and 27.5 for horizontal and vertical planes, respectively. Performance of the microbeam system was tested by beam scanning across the surface of a copper mesh sample (1000 lines/inch) and measuring the X-ray spectrum. A beam spot size of 2 x 2 μm2, which is larger than the design goal, is currently obtained. We are now adjusting the whole system to achieve a beam spot size of 1 x 1 μm2