Energy transport processes in dense plasmas heated with intense thermal x-rays

自1982年以来，我们与德国马克斯-普朗克量子光学研究所合作，研究了激光产生x射线的物理学及其在腔内的限制。在x射线绝对谱测量技术、高密度等离子体辐射输运物理、辐射流体力学等方面取得了重大进展。证明了激光产生的辐射在腔内的约束，并实现了2.5兆开尔文的普朗克辐射，这是实验室最高的辐射温度。本财政年度研究了激光产生的x射线产生的高密度等离子体中的能量输运物理，特别是辐射热波、冲击波和再发射的传播，并对其工业应用进行了探讨。从高强度x射线产生的工业应用角度出发，大阪大学激光工程研究所和马克斯-普朗克量子光学研究所组织了日德飞秒激光器和高强度应用研讨会。主要议题如下：(1)惯性约束聚变中的飞秒激光(2)固体表面谐波的产生(3)飞秒激光的发展(4)气体中的谐波产生(5)皮秒和飞秒激光脉冲传播(6)相对论性激光与等离子体相互作用的数值模拟(7)固体对飞秒激光脉冲的吸收(8)相干和非相干x射线及其诊断(9)高强度场中的原子物理学。为了解激光在工业上的应用现状，工作坊结束后，我们参观了汉诺威工业大学、汉诺威激光中心、柏林工业大学、Max-Born研究所等工业企业。

Since 1982, collaborating with Max-Planck Institute of Quantum Optics in Germany, we have studying the physics of the generation of x-ray with lasers and its confinement in a cavity. We have made great progress on the measurement technique of absolute x-ray spectrum, the physics of radiation transport in high density plasmas and radiation hydropynamics. The confinement of the laser produced radiation in cavity has demonstrated and the Planck-radiation of 2.5Mega-degree Kelvin, which is the highest radiation temperature in laboratory, has achieved. In this fiscal year, the physics of the energy transport in high density plasmas produced by laser-produced x-ray, especially, propagation of radiation thermal wave, shock wave, and reemission are studied, and its industrial application is also investigated.From the view point of the industrial application of the high intense X-ray generation, the Japanese-German workshop on Femtosecond Lasers and High-Intensity Applications was organized by Institute of Laser Engineering, Osaka University and Max-Planck Institute of Quantum Optics. The main topics were as follows.(1) Femtosecond lasers in inertial confinement fusion(2) Harmonic generation from solid surfaces(3) Femtosecond laser development(4) Harmonic generation in gases(5) Pico-and femtosecond laser pulse propagation(6) Numerical simulation of relativistic laser-plasma interaction(7) Absorption of femtosecond laser pulses by solids(8) Coherent and incoherent x-rays and their diagnostics(9) Atomic physics in high intensity fieldTo investigate the project LASER2000 on Germany, and to know the status-quo of the laser application in industry, after the workshop, we have visited Hanover Technical University, Hanover Laser Center, Berlin Technical University, Max-Born Institute, and som industrial companies.