Alignment and bonding of silicon mirrors for high-resolution astronomical x-ray optics

Recent advances in the fabrication of silicon mirrors and their alignment and integration methods make it possible to build large-area, lightweight, high-resolution x-ray telescopes with arc-second angular resolution. Such a telescope, having simultaneously arc-second resolution and large (> 1 m2 ) collecting area, has never been built before and it will revolutionize high energy astronomy. For such optics, the challenges are twofold: fabrication of high quality mirror segments and precise integration of thousands of these mirrors to a common sharp focus. In this paper, we address the technology for the mirror integration carried out at Goddard Space Flight Center and report the recent result of making such high-resolution optics. We address the crucial technology components: positioning a mirror, measuring its focus, adjusting its mount pointsto optimize the focus, bonding the mirror, and co-alignment of mirrors. We also present the latest x-ray test results that demonstrate the efficacy of such methods and address areas for further improvement. Presently, mirrors built this way have a resolution of 2²-3² HPD (half-ower diameter).

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