A Study of Interstellar Large Organic Molecules Explored with Near-infrared High-resolution Spectroscopy

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K17669
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan (2018-2019); Kyoto Sangyo University (2016-2017)
• Principal Investigator: Hamano Satoshi 国立天文台, TMTプロジェクト, 特任研究員 (70756270)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: 星間有機分子 / 赤外線高分散分光 / フラーレン / 星間物質

Outline of Final Research Achievements

In order to identify of the carrier molecules of diffuse interstellar bands (DIBs), which are expected to be an important tool to investigate the interstellar organic molecules, I conducted a observational study of DIBs in the near-infrared (NIR) wavelength range, in which the DIBs have not been fully investigated. First, I developed a data reduction pipeline software for the NIR high-resolution spectrograph WINERED, which was mainly used in this study. I collected the near-infrared spectra of a lot of targets, and investigated the environmental dependence of NIR DIBs and its intrinsic profiles. As a result, I succeeded to reveal the properties of the carriers of NIR DIBs. In addition, I also succeeded to detect the NIR absorption bands originated from interstellar C2 and CN molecules for the first time.

Free Research Field

赤外線天文学

Academic Significance and Societal Importance of the Research Achievements

宇宙における生命の発生過程や惑星系の素となるダストの性質を調べる上で、星間ガス雲中における複雑な有機分子の反応過程や分布は重要である。本研究では、フラーレンやPAHといった巨大な有機分子を調べる道具として期待されているDIBの分子同定に向けて重要な手がかりをいくつか得ることに成功した。本研究を足がかりとしてDIBの同定が成功すれば宇宙における有機分子を探る新たなツールを手に入れることとなり、宇宙化学、宇宙生物学の大きな進展が期待される。