Advanced study on short X-ray transients with MAXI alerts

2023 Fiscal Year Final Research Report

• Project/Area Number: 19H01946
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 16010:Astronomy-related
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Mihara Tatehiro 国立研究開発法人理化学研究所, 開拓研究本部, 専任研究員 (20260200)
• Co-Investigator(Kenkyū-buntansha): 根來 均 日本大学, 理工学部, 教授 (30300891)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 宇宙科学 / 宇宙物理 / 国際宇宙ステーション / MAXI / X線天文学

Outline of Final Research Achievements

In order to explore short-time (less than 1 hour) regions with X-rays (less than 10 keV), which remains as a discovery space in the time-domain astronomy, we came up with the idea of linking our wide-field X-ray monitoring device MAXI and the narrow-field X-ray telescope NICER which is also on the ISS. We realized the link with this research funding.
Previously, follow-up observation via the ground route took about a day, but by improving communication routes and software, we succeeded to shorten the time to about three hours at the earliest. We also proceeded the on-orbit hook-up of MAXI and NICER (OHMAN), and it was realized in August 2022. As a result, we can now perform follow-up observations of new MAXI novae in less than 10 minutes, which previously took more than 3 hours.

Free Research Field

X線天文学

Academic Significance and Societal Importance of the Research Achievements

我々はまず全天X線監視装置MAXIの３年間の運用を行った。これにより82件の天文学電報Atelと103件のガンマ線バースト連携ネットワークGCNへの速報を行うことができ、世界の突発天体天文学界に貢献した。MAXI-NICER連携では、地上経由(MAXI and Nicer Ground Alert: MANGA)の枠組みを構築し、追観測までの時間を３時間までに短縮した。これによりRSCVn連星のフレアなどの天体現象を迅速に観測できるようになった。またOHMANも開通した。これはISS上の異なる２国間の観測機器を結合させた点と、ISS上での情報伝達方法を実現した点で意義があったと評価されている。