High-resolution X-ray microbeam by using a Kirkpatrik-BaezType mirror at SPring-8

X-ray microbeam generated by a Kirkpatrik-Baez (KB) mirror optics with a set of two parabolic-shaped reflective surfaces was tested at an undulator beamline BL47XU of SPring-8. The KB mirror used in the experiment was fabricated by numerically-controlled polishing technique at Cannon Co. Ltd. Measured focal spot size at the x-ray energy of 8 keV in the vertical and the horizontal were 0.75 $\mu$m and 0.32 $\mu$m, respectively. The photon flux of the focal spot was $2 \times 10^{10}$ [photons/ s/100 mA ring current]. Tantalum test pattern of the 0.2 $\mu$m line width was clearly observed with raster scan