Single-shot X-ray phase-contrast imaging of dense plasmas

稠密等离子体的单次X射线相衬成像

• 批准号: 452935060
• 负责人: Professor Dr. Stefan Funk
• 金额: --
• 依托单位: GSI Helmholtzzentrum für Schwerionenforschung GmbH
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/452935060?language=en
• 关键词: Single; shot; ray; phase; contrast

The investigation of laser-driven shock phenomena is a topical field of research of matter at extreme conditions. Within this project, we will investigate phenomena like laser-driven blast waves interacting with dense obstacles, low-entropy compression using reflecting shocks and studies of radiative preheat in laser-shock experiments and rapid radiation heating as a means to generate high density matter states. For dense plasma, visible photons give access to the surface of the matter distribution only, while X-rays offer the opportunity to image the 3D morphology of the matter distribution. In the case of small density variation as typically the case in laboratory experiments, X-ray phase-contrast enables higher image contrast than standard X-ray attenuation. In this project we will investigate grating-based X-ray phase-contrast methods for the imaging of the above mentioned laser-driven shock phenomena at the high power laser PHELIX at GSI. Challenging aspects are the stability and alignment of the imaging system, the optimization of the Talbot parameters for moiré imaging and the image analysis. Simulations will be performed to generate realistic density distributions, to propagate X-rays through such targets and to simulate image signatures. The comparison of simulated and measured data will be employed to quantify the results.

激光驱动冲击波现象的研究是极端条件下物质研究的热点领域。在这个项目中，我们将研究激光驱动的冲击波与密集障碍物相互作用，使用反射冲击的低熵压缩和激光冲击实验中的辐射预热研究以及快速辐射加热作为产生高密度物质状态的手段等现象。对于致密的等离子体，可见光子只能进入物质分布的表面，而X射线提供了对物质分布的3D形态进行成像的机会。在小密度变化的情况下，如在实验室实验中的典型情况，X射线相衬能够实现比标准X射线衰减更高的图像对比度。在这个项目中，我们将研究基于光栅的X射线相衬方法，用于在GSI的高功率激光器PHELIX上对上述激光驱动的冲击现象进行成像。主要包括成像系统的稳定性和准直性、莫尔成像的塔尔博特参数优化以及图像分析。将进行模拟，以生成真实的密度分布，通过这些目标传播X射线，并模拟图像签名。模拟和测量数据的比较将被用来量化结果。