Unraveling the Nature of Radio Jets Governing the Formation of Massive Galaxies

2022 Fiscal Year Final Research Report

• Project/Area Number: 21K13968
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 16010:Astronomy-related
• Research Institution: National Astronomical Observatory of Japan
• Principal Investigator: Yamashita Takuji 国立天文台, ハワイ観測所, 特任研究員 (20800759)
• Project Period (FY): 2021-04-01 – 2023-03-31
• Keywords: 銀河 / 活動銀河核 / ブラックホール / 電波 / 赤外線 / 大規模データ

Outline of Final Research Achievements

The nature of massive galaxies suggests that they were already formed in the early universe, and radio-jets emitted by radio galaxies are strong candidates for the mechanism that halts their further mass growth. However, exploration of radio galaxies in the distant universe has been limited so far, and the understanding of the relationship between the formation of massive galaxies in the early universe and radio-jets has been inadequate. This research aims to pioneer the exploration of radio galaxies in the early universe using data from the Subaru Hyper Suprime-Cam survey and wide-field radio surveys, in order to elucidate the relationship between the formation of massive galaxies in the early universe and radio jets. In this project, we constructed, for the first time, a sample of distant radio galaxies with a redshift of 4 or higher and conducted follow-up spectroscopic observations, revealing the large-scale structures associated with these distant radio galaxies.

Free Research Field

天文学

Academic Significance and Societal Importance of the Research Achievements

現在の宇宙に存在する全星質量の多くを占める大質量銀河の形成と進化を解き明かすことは天文学の一大課題である。本研究では、最新のすばる望遠鏡Hyper Suprime-Camサーベイデータと電波サーベイデータを活用することで、高赤方偏移での電波銀河サンプル構築方法を確立した。本研究が先駆けとなり、本手法による遠方電波銀河探査と関連する研究が国内外で始動し、停滞していた遠方電波銀河探査を打開することができた。