The Metallicity Distribution of the Milky Way using Variable Stars

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H07323
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Single-year Grants
• Research Field: Astronomy
• Research Institution: Kyoto Sangyo University
• Principal Investigator: FUKUE Kei 京都産業大学, 神山天文台, 研究員 (20785753)
• Project Period (FY): 2016-08-26 – 2018-03-31
• Keywords: 恒星 / 変光星 / 化学組成

Outline of Final Research Achievements

For detailed analysis of stellar chemical abundances, high-resolution spectra in the optical have been mainly used, while recent development of near-infrared (near-IR) spectrometers has opened new wavelength windows. The severe foreground reddening towards the Galactic plane, especially in the direction of the Galactic Center requires observation in the IR windows. Therefore, the goals of this study are twofold: (1) to establish the method of determining stellar atmospheric parameters and (2) to estimate iron and other elemental abundances of Cepheids. We obtained high resolution and high quality spectra of well-studied stars, using WINERED. We invented new methods of determining effective temperatures, microturbulences and the iron abundances. We are going to relocate WINERED to large diameter telescope.

Free Research Field

天文学

Academic Significance and Societal Importance of the Research Achievements

最近の近赤外線観測装置の発達により減光の強い銀河系中心領域を見通す事が可能となり、銀河系中心領域やバルジ、ディスクの広い範囲にわたって、セファイドを含む様々な恒星が同定され始めている。そのような天体に対して、本研究で構築した手法を適用させることで、天体ごとの有効温度や金属量を導出することができる。そのようにして得られた各天体の物理情報から、銀河系の進化や星形成史の解明につながることが期待される。