Development of a new high-dispersion spectrometer for unveiling exoplanet atmosphere

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K13468
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Astronomy
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: Kotani Takayuki 国立天文台, 太陽系外惑星探査プロジェクト室, 助教 (40554291)
• Co-Investigator(Renkei-kenkyūsha): KAWAHARA Hajime 東京大学, 大学院理学系研究科, 助教 (90649758) ; MURAKAMI Naoshi 北海道大学, 大学院工学研究院, 助教 (80450188)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 太陽系外惑星 / 高分散

Outline of Final Research Achievements

For future direct high-resolution spectroscopic observation to unveil atmosphere composition of Earth-like planets, it is required to increase efficiency of a spectrometer at least a few times, as well as a certain amount of spatial resolution. In this study, we investigated Fourier spectrometer as a solution to these problems. We developed a monolithic, aluminum step mirror to achieve spectrometer without any active mechanism. Spectral resolution up to 30000 requires 30 steps, 204um depth, 10x10mm dimension and our newly developed mirror almost satisfies our specifications. We also designed a step mirror to achieve spectral resolution up to 100000 for spectroscopic observation of the Earth-like planets. Furthermore, we carried out laboratory demonstration of high-contrast spectroscopic observation by combining the Fourier spectrometer with a coronagraphic instrument for eliminating glaring light from a parent star to direct observation of the Earth-like planets.

Free Research Field

太陽系外惑星