Space Sciences/Astrophysics Seminar with Brandon Chalifoux on Assembly and Alignment of X-ray Telescope Mirror Segments

X-ray telescopes serve as critical tools for observing the high-energy universe, but opto-mechanical design challenges have so far limited their imaging and spectroscopic performance. I will describe our efforts toward solving the severe opto-mechanical challenge of assembling and aligning tens of thousands of mirror segments, with nanometer accuracy, as will be required for future X-ray observatories.  

Several areas of future study with X-ray telescopes include observation of the earliest black holes, high-resolution characterization of the baryonic component of the Cosmic Web, and energetic activity of stars and star-forming regions. Observations will require high sensitivity to observe faint and diffuse objects, and high imaging resolution to distinguish nearby objects or resolve fine features. High sensitivity requires large effective area of the telescope optics, and high resolution requires nanometer-accurate optical surfaces. It is now possible to  fabricate high-quality thin mirror segments to achieve both goals simultaneously, but assembling and aligning them into a telescope that survives launch remains a severe challenge.  

Our approach to assembly and alignment uses ultrafast lasers to adjust alignment of mirror segments after bonding, by creating microscopic strained regions, which enables an over-constrained mounting scheme to provide high strength bonds and optical accuracy simultaneously. I will describe our approach and recent progress toward assembling and testing stacks of X-ray mirrors.

Sponsored by the McDonnell Center for the Space Sciences.