2019 Fiscal Year Final Research Report
Verification of eruptive mass loss scenario in red supergiants
| Project/Area Number |
16K05306
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Astronomy
|
|---|
| Research Institution | National Astronomical Observatory of Japan |
|---|
Principal Investigator |
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
中川 亜紀治 鹿児島大学, 理工学域理学系, 助教 (60535631)
|
|---|
| Project Period (FY) |
2016-04-01 – 2020-03-31
|
| Keywords | 赤色超巨星 / 質量放出 / 恒星光球面撮像 / サブミリ波干渉計 / ALMA望遠鏡 / 高角度分解能観測 |
|---|
| Outline of Final Research Achievements |
A red supergiant (RSG) is in the final stage of a stellar evolution for a heavier star than eight solar mass. In this stage, stellar nucleosynthesis materials are largely ejected from its photosphere. The materials may gravitationally be bounded later in a galaxy to form new stars possibly with earth-like planets and life. RSG's mass ejection, in other words, mass loss, is considered to be a very important process for a chemical evolution in the universe. In the corse of this research of RSGs' mass loss process, we have achieved the highest angular resolution of ALMA, one of the greatest telescopes in the world, to observe one of the most famous RSGs VY CMa whose distance is 3600 light years. We successfully captured the photosphere in a sub-millimeter wave region as well as the gas and dust anisotropically ejected from the RSG.
|
| Free Research Field |
電波天文学
|
| Academic Significance and Societal Importance of the Research Achievements |
赤色超巨星の質量放出は、中小質量星の進化末期段階である漸近巨星分岐星（AGB）の延長線上で議論されることが多く、その質量とサイズがAGB星とは桁で異なるため3次元流体力学シミュレーションすらも難しい現象であり、その理解はAGB星と比較して相対的に不足している。RSGにはAGB星とは明らかに異なる「間欠的な質量放出」の特徴が潜むことがこれまで見過ごされており、本研究成果はRSGの質量放出機構を大きく見直す機会となる。また、本研究の過程において行ったALMAのサブミリ波最高角度分解能性能実証により2021年からの一般観測でその性能が利用可能となり、サブミリ波天体物理研究への波及効果は極めて大きい。
|
