Design optimization of highly accurate elliptical mirrors for hard-x-ray microfocusing probes at SPring-8

Abstract

This paper presents the design and implementation of focusing optical systems using total reflection mirrors that are customized into three hard x-ray beamlines for four experimental groups at SPring-8. First, for the BL46XU Engineering Science Research III beamline, we designed a vertical focusing mirror and a manipulator to create a high-intensity 20- μm focusing beam, that improves the sensitivity for hard x-ray photoemission spectroscopy. Second, for the BL39XU Magnetic Materials beamline, we designed two pairs of Kirkpatrick-Baez (KB) mirrors and corresponding manipulators for sub-micron focusing and 15 × 15 μm² high-intensity focusing; these were designed in order to use X-ray magnetic circular dichroism (XMCD) spectroscopy for two-dimensional high-resolution mapping of magnetism and XMCD experiments under high pressures (~10 GPa). Third, for the BL32XU RIKEN Targeted Proteins beamline, we designed KB mirrors for focusing at 1 × 1 μm²; these were designed for carrying out the structural analysis of microcrystal proteins in cooperation with RIKEN SPring-8 Center. These elliptical mirrors and manipulators are currently in the process of being manufactured, and their installation on the beamlines is underway. In this paper, we describe the design considerations, optimized design of the optical system, and installation progress on the beamlines.