Proof of fast ignition scheme using Super-penetration of laser light

2019 Fiscal Year Final Research Report

• Project/Area Number: 15H05751
• Research Category: Grant-in-Aid for Scientific Research (S)
• Allocation Type: Single-year Grants
• Research Field: Plasma science
• Research Institution: Osaka University
• Principal Investigator: Tanaka Kazuo 大阪大学, 先導的学際研究機構, 特任教授(常勤) (70171741)
• Co-Investigator(Kenkyū-buntansha): 羽原 英明 大阪大学, 工学研究科, 准教授 (60397734) ; 長友 英夫 大阪大学, レーザー科学研究所, 准教授 (10283813) ; 坂上 仁志 核融合科学研究所, ヘリカル研究部, 教授 (30254452) ; 城崎 知至 広島大学, 工学研究科, 准教授 (10397680)
• Project Period (FY): 2015-05-29 – 2020-03-31
• Keywords: 高速点火 / レーザー自己集束 / 高速電子

Outline of Final Research Achievements

The purpose of this research project is to apply the super-penetration (SP) phenomenon, in which a laser light penetrates in a high-density plasma exceeding the critical density points via relativistic and optical pressure effects, to fast-ignition laser fusion, and to demonstrate heating on a large-scale implosion fuel core. In this project, we, 1. developed several measurement techniques necessary for observation of SP mode in over critical density plasma, 2. successfully showed a stable formation of plasma channel capable of transporting heating energy to the fuel core, and 3. developed a large-scale parallel simulation code allowing real scale and real time calculation equivalent with the experiments. Based on these results, about 1% heating efficiency (energy coupling) in large-scale imploded spherical plasma was demonstrated. By applying methods to reduce divergence angleｓ of fast electrons we can prospect heating efficiency of 10% or more that is necessary for practical use.

Free Research Field

プラズマ科学

Academic Significance and Societal Importance of the Research Achievements

点火級の大規模プラズマに対し、プラズマチャンネルを安定的に形成し、核融合点火に必要なエネルギーを燃料コア近傍まで輸送可能なことを示した。更に効率的に加熱する手法を開発し実用レベルの加熱効率が実現可能である見通しがたち、本研究課題の有用性と核融合エネルギー実現の道筋を示すことができた。