Thermal evolution models of giant planets: effect of gas accretion onto protoplanets

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K14542
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 17010:Space and planetary sciences-related
• Research Institution: Kurume University
• Principal Investigator: Kunitomo Masanobu 久留米大学, 医学部, 講師 (20794621)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 原始惑星系円盤 / 惑星形成 / 降着 / 原始星 / 太陽 / ニュートリノ

Outline of Final Research Achievements

We focused on the evolution of protoplanetary disks where planets are formed and obtained three results. First, by combining long-term disk evolution calculations and stellar evolution calculations, we revealed the crucial role of the irradiation of high-energy photons from the central star. Next, we focused on the evolving composition of the protoplanetary disk gas and investigated the consequences of the accretion of the protosolar disk gas onto the young Sun. We found that the accretion can be imprinted in the solar interior as a larger compositional gradient than the standard solar models. Third, we found that the model with accretion matches observed neutrino fluxes, meaning that accretion can be the solution to the "solar modeling problem", which has been studied over the last two decades in solar physics. This is an interdisciplinary result resolving the issue in solar physics with star and planet formation processes.

Free Research Field

理論天文学

Academic Significance and Societal Importance of the Research Achievements

学術的意義は，これまで必ずしも考慮されてこなかった星と円盤の共進化過程に注目した学際性・新規性にある。原始惑星系円盤の進化に中心星の進化が重要であること，逆に円盤からの降着が中心星の進化に影響することを解明した。太陽物理の問題を，最新の星形成・惑星形成・原始惑星系円盤・恒星進化の理解を総動員し解決策を示した。太陽の形成・進化の理解という天文学・素粒子物理学の複数の分野にわたる重要な問題を解決したことに学術的意義がある。
本研究の社会的意義は，地球のような惑星の誕生の理解に必要不可欠な原始惑星系円盤の進化過程，もっとも身近な恒星である太陽の誕生・進化過程の理解を進める貢献をしたことにある。