Study on the protoplanetary disk structure based on high-resolution mid-infrared observations

2019 Fiscal Year Final Research Report

• Project/Area Number: 15H05439
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Astronomy
• Research Institution: Okayama University of Science (2018-2019); Kurume University (2016-2017); Kanagawa University (2015)
• Principal Investigator: Honda Mitsuhiko 岡山理科大学, 生物地球学部, 准教授 (40449369)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 光赤外線天文学 / 原始惑星系円盤

Outline of Final Research Achievements

We made high-resolution mid-infrared imaging observations of the protoplanetary disks around Herbig Ae/Be stars mainly using mid-IR instruments COMICS on Subaru Telescope. Based on our continuous observational studies, we established a new interpretation that the disks around the group I Herbig Ae/Be stars are actually transitional disks. In addition, we found that the misalignment of the inner and outer disks affects the mid-infrared disk morphology significantly.
Furthermore, we have been developping an internal cold chopper system for the future
next-generation ground-based mid-IR facility/instrument. A first test model was designed and fabricated for detailed analysis and trouble shooting. We found some problems on the first test model, but also noticed that even this model can be used for the chopping observations. We are now making a second test model and also planning an on-sky test observing with these new cold chopper.

Free Research Field

光赤外線天文学

Academic Significance and Societal Importance of the Research Achievements

我々の原始惑星系円盤の中間赤外線観測により、group I に属するHerbig Ae/Be型星原始惑星系円盤はフレア円盤であるという解釈を、遷移円盤に相当するという正しい解釈を示すことが出来た。これは現在のALMAの高解像観測によってもほぼ確認されている。
また、冷却チョッパーの開発は、日本が次世代地上中間赤外線装置開発において国際貢献をしていくための重要な技術の一つとなりうる。また、日本の赤外線観測コミュニティにとっても有用なデバイスとなると期待している。