Innovation in time-domain astronomy by X-ray optics with high-precision microfabrication

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K20525
• Research Category: Grant-in-Aid for Challenging Research (Pioneering)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 15:Particle-, nuclear-, astro-physics, and related fields
• Research Institution: Kanazawa University
• Principal Investigator: Yonetoku Daisuke 金沢大学, 数物科学系, 教授 (40345608)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: X線光学系 / 微細加工 / ガンマ線バースト / X線天文学

Outline of Final Research Achievements

Aiming to avoid deterioration of imaging performance due to elementary deformation, which has been a manufacturing problem of conventional lobster-eye optics (LEO), we constructed an LEO on a glass flat plate by 3D laser micro-machining and magnetohydrodynamic polishing. We were able to obtain X-ray imaging performance of about 10 arcmin squared, which is equivalent to that of conventional LEOs. However, to achieve higher precision, the surface roughness by laser processing needs to be reduced by one order of magnitude or more. The technology to array multiple LEOs to achieve a wide field of view has made great progress. Using collimator light, the effective focal length of LEOs was measured, and making a mechanical adjustment of several 10 microns, we successfully constructed wide-field imaging optics which can be achieved with performance comparable to one of single LEO.

Free Research Field

宇宙物理学

Academic Significance and Societal Importance of the Research Achievements

宇宙物理学・天文学では、「広い視野を持った観測装置による広域探査・モニター」と「狭い視野で高感度な大型望遠鏡による詳細観測」が協調することで宇宙の観測可能領域を拡大し、真理を追求している。とりわけ、高エネルギー宇宙物理学における広視野観測では、全天の1/10以上にもおよぶ広域をモニターすることで突発天体の発見に貢献してきた。 本研究により、最先端の観測を実現するために必要な約1.5桁の観測感度の改善が見込める基盤技術が得られ、同時にさらなる課題を確認した。この技術は、トンネル・橋・建造物などの非破壊検査を圧倒的に高効率化することにも寄与でき、産業界においてもインパクトのある開発である。