Ultra-fast probing of solid target heating by intense-laser irradiation using X-ray free electron lasers

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K03788
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 14010:Fundamental plasma-related
• Research Institution: Japan Synchrotron Radiation Research Institute
• Principal Investigator: Yabuuchi Toshinori 公益財団法人高輝度光科学研究センター, XFEL利用研究推進室, 主幹研究員 (20397772)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 高エネルギー密度科学 / 高強度レーザー / X線自由電子レーザー / プラズマ

Outline of Final Research Achievements

The purpose of the proposed research is to study the solid heating processes in ultra-intense laser-solid interactions. The development of a new method has been proposed in this project to investigate the spatially and temporally resolved information of the ionization degrees of the laser-heated sample. In the method, the ionization degree of the laser-heated matter is diagnosed by the spectroscopy of characteristic X-rays produced by a probe pulse of the X-ray free electron laser. At an early stage of this research, the background noise in the spectroscopy has been realized as a challenge for the realization of the proposed method. Therefore, a new target design has been developed to minimize the background. The newly developed targets have reduced the noise while keeping the signal level successfully.

Free Research Field

高エネルギー密度科学

Academic Significance and Societal Importance of the Research Achievements

微小な時間及び空間領域に高いエネルギーを集中させることができる高強度レーザーは，固体を瞬時にプラズマ化し高いエネルギー密度状態を形成する．この物質状態は空間的に非一様で極めて高速に変化する．このような物質状態の理解は，現在においては主に数値計算に依存しており，実験的には十分に調べられていない．新たな診断手法を開発することで，非平衡な物質状態を超高速高精細に実験的に測定することは，数値計算の確かさを検証し計算の高精度化を支援すると同時に，高エネルギー粒子源，レーザー材料加工などの応用利用の高度化に寄与するものと強く期待される．