Development of four-reflection X-ray telescope for the study ofmsmologicalwarm-hotintergaladcticmedium

温热星系际介质（WHIM）是研究由未知基本粒子组成的暗物质形成的大尺度宇宙结构的重要探测器。WHIM也是阐明迄今为止很少观测到的暗重子结构和演化的重要观测目标。在本研究中，我们开发了一种新型的x射线望远镜来探测来自WHIM的弱x射线，首先我们以四个反射镜系统作为基础光学系统，并建立了射线追踪代码来分析这些新型光学系统，包括扩展的Wolter I型光学系统。利用该工具，在假定卫星和探测器结构的条件下，优化望远镜参数，如焦距、单元镜的直径和长度以及次要表面材料，以最大限度地提高有效面积、视场、GRASP和角分辨率等性能。在此基础上，我们利用先前为铃木公司制作的分段复制箔机制作了四反射望远镜的象限模型。此外，我们开发了超抛光复制芯轴和多级全壳小衬底，以获得更高的复制箔小性能，并减少元素镜的总数。在芯棒上实现了图形误差小于0.5 μm，表面微韧性小于1 nm。在单片反射镜基板上，我们尝试了几种方法，发现可以采用直接加工的方法制作出图形误差在10 μm以内的单片反射镜基板

The warm-hot intergalactic medium (WHIM) is an important probe to study large scale structure of the universe fomedby the dark matter, which consists of unknown elementary particles. WHIM is also important observation target to clarify the structure and the evolution of dark baryons, which have been hardly observed so far. In this research, we developed a new type of X-ray telescope to detect weak X-rays from WHIM At first we took four reflection mirror system as abase optics and established ray tracing code for analyzing these new optical systems including extended Wolter type I optics. Using this tool, we optimized telescope parameters such as focal length, diameters and length of element mirrors and minor surface materials to maximize performances such as an effective area, a field of view, GRASP and angular resolution under the condition of assumed satellite and detector structures. Based on this study we made a quadrant model of four-reflection telescope using segmented replica foil miner made by previously used method for Suzuki. Adding to this, we developed superpolished replica mandrel and multistage full shell minor substrate to get higher performance of a replica foil minor and reduce total number of element mirrors. On the mandrel, it was achieved that figure error was has than 0.5 μm and surface microtoughness was less than 1 nm. On the monolithic mirror substrate, we tried several methods and found that a direct machining method can be used to make such substrate with figure error of 10 μm Technologies developed in this research can be utilized to make telescopes for future satellite mission such as the DIOS