Microscale radiography of complex hydrodynamics phenomena in high-density laser plasma

于2022财政年度，我们在SACLA XFEL（BL 3）的高能量密度平台上进行了4个已接受提案的帧中的相衬成像（PCI）实验。我们的PCI方法进一步升级。现在，射线照相方案在多成像采集机制中操作。在从物体到探测器的三个不同距离处记录物体的图像。在每一个距离上，PCI效应都针对物体的特定吸收和散射特性进行了优化。该改进允许在宽的密度变化范围内提高射线照相的质量和信息量，并增加密度测量的准确性。通过该方法，本文研究了在高达几兆巴的压力下，高能激光对许多晶体和非晶体材料所产生的复杂冲击波的形貌，为精确确定状态方程参数提供了理论依据。和天体物理学相关的任务（阿尔法石英，z切石英，熔融石英，铝，镁硅酸盐Mg2SiO4，MgSiO2玻璃陶瓷）。我们继续研究冲击诱导的现象，特别是在金刚石的滑动破坏机制。在三种不同取向的金刚石晶体中<100><110>，<111>研究了冲击波诱导缺陷介导的塑性差异，在理论和模拟中，对于金刚石中的弹塑性冲击波分裂动力学，使用光滑粒子流体动力学（Smoothed Particle Hydrodynamics）程序的二维模拟获得了令人印象深刻的匹配。发展了基于衍射的激波上升波前宽度测量模型。

During 2022 FY year we performed phase-contrast imaging (PCI) experiments at High Energy Density platform of SACLA XFEL(BL3) in the frames of 4 accepted proposal. Our the PCI method was further upgraded. Now the radiographic scheme operates in multi-imaging acquisition regime. The images of the object are recorded at three different distances from the object to detectors. At every distance the PCI effect is optimized for the specific absorption and scattering properties of the object. That improvement allowed to advance the quality and informative of radiography in the wide range of density variations and to increase the accuracy of density measurements.By this method, we studied the complicated morphology of the high-energy-laser-induced shocks formed under pressure up to a few Mbar for numerous crystalline and amorphous materials of interest of precise determination parameters for equations of state (EOS) and for astrophysics related tasks (alfa-quartz, z-cut quartz, fused silica, Al, magnesium silicate Mg2SiO4, MgSiO2 glass ceramic).We continued investigation of shock induced phenomena in diamond, in particular, the slip failure mechanism. In crystalline diamonds with three different orientations <100>, <110>, and <111> were examined on the difference in plasticity mediated by shock-induced defects.In theory and simulations, for dynamic of elastic-plastic shock waves splitting in diamond the impressive matching obtained by 2D modeling using Smoothed Particle Hydrodynamics code. Developed the diffraction based model for measuring width of rising front in shock waves.