The evolution of massive stars toward supernovae: from the last century to the final year

2020 Fiscal Year Final Research Report

• Project/Area Number: 17H02864
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Astronomy
• Research Institution: Kyoto University
• Principal Investigator: Maeda Keiichi 京都大学, 理学研究科, 准教授 (00503880)
• Co-Investigator(Kenkyū-buntansha): 諏訪 雄大 京都産業大学, 理学部, 准教授 (40610811) ; 勝田 哲 埼玉大学, 理工学研究科, 助教 (50611034) ; 守屋 尭 国立天文台, 理論研究部, 助教 (90779547)
• Project Period (FY): 2017-04-01 – 2021-03-31
• Keywords: 理論天文学 / 光赤外天文学 / 多波長天文学 / 超新星爆発 / 恒星進化

Outline of Final Research Achievements

The theory of stellar evolution forms the basis of astronomy. However, the nature of massive star evolution has not been clarified. In this project, we have performed comprehensive study on the stellar evolution and the supernova (SN) explosoin, both in observatoins and throry. Our goals were the following: (1) uncovering the nature of stellar evolution in the final phase through SN observations, (2) connecting the nature of the final stellar evolution and that of the SN explosion, and (3) comprehensively understanding the unclarified issues in the massive star evolution. We have obtained various new insight, some of which are hilighted below: we discovered that a large fraction of massive stars experience a dinamically-driven huge mass loss in the final century before the SN. Further, we have discovered the moment of the explosion for one SN, and a very high ejecta velocity for an SN associaetd with a gamm-ray burst, among other outcomes from this project.

Free Research Field

理論・観測天文学

Academic Significance and Societal Importance of the Research Achievements

大質量星の進化は天文学の様々な分野における基礎であると同時に、進化最期に引き起こされる大爆発である超新星は様々な物理過程・物理法則の研究の場となる。本課題では、大質量星の最終進化と超新星爆発の未解明問題について、理論・観測を融合させ様々な視点から研究を行った。大質量星の大部分は爆発直前に大規模な質量放出を伴うという発見や、長年理論的に予測されていたが確固たる証拠の無かったショックブレークアウト現象の発見など、大質量終末期進化と超新星の理解の基礎となる様々な知見を得た。