Application of coherent x-rays using new soft x-ray interferometer

提出了一种新的软X射线干涉仪，它采用两个透射光栅作为分束器。我们继续通过提升双靶配置中的X射线激光增益来开发相干X射线源。相干X射线源的研究也取得了进展。微通道板是X射线干涉系统中重要的二维探测器，本文研究了微通道板中软X射线探测的理论模型。主要研究结果如下：1.构建了透射光栅软X射线干涉仪。实验结果表明，采用He-Ne激光作为干涉仪的光学系统是可行的。观察到预期的条纹图案。配备了电机驱动光学元件系统，可在真空中精确调整光轴，位置精度为0.5 μm，角度为5 μrad。在光学对准完成后，将进行软X射线干涉仪的测量。2.对不同结构的X射线激光源输出的X射线光束的横向相干性进行了测量。首次观察到Al Xi 3d-4f（15.47 nm）激光谱线的空间相干性随着放大的进行而提高。另一方面，在15 nm附近，非激光谱线的强度几乎保持不变，尽管它们的强度随着等离子体长度的增加而增加。3.利用同步辐射研究了真空紫外（VUV）波段（波长范围20-80 nm）的微通道板（MCP）探测X射线的电流响应特性。计算从一个简单的模型来考虑MCP的检测电流进行了比较与测量的MCP响应的入射角依赖性。结果表明，在一个通道内的X射线反射的影响是重要的了解在真空紫外区的MCP的检测过程。

A newly proposed interferometer for soft x-ray in which two transmission gratings are used as beam splitter has been developed. We continued to develop coherent x-ray source by upgrading x-ray laser gain in the double target configuration. Investigation of coherent x-ray source has also been progressed. Theoretical model of soft x-ray detection in microchannel plates, which are important as 2-D detectors in the x-ray interferometric system, has been considered. The main results are as follows :1.The soft x-ray interferometer with transmission grating has been constructed. An experiment was performed to show feasibility the same optical system as the proposed interferometer by using a He-Ne laser light. An expected fringe pattern was observed. A motor drive optical component system has been equipped and makes us possible to adjust optical axis precisely in vacuo with position accuracy of 0.5 μm and angle of 5 μrad. Soft x-ray interferometer will be performed after optical alignments have been completed.2.Measurements on transverse coherence of x-ray beam from our x-ray laser source with various configurations have been performed. It was observed that the or spatial coherence was improved as its progress of amplification for the Al XI 3d-4f line (15.47 nm), one of the lasing lines in our experiment, for the first time. On the other hand, visibilities remained almost constant for the non-lasing lines around 15 nm, although their intensities grew with the plasma length.3.The current response characteristics of microchannel plates (MCPs) for detection of x-rays have been investigated using synchrotron radiation in the vacuum-ultraviolet (VUV) band (the wavelength range 20-80 nm). Calculation from a simple model to account the detection current of MCP were compared with the measured incident angle dependence of MCP response. The result indicates the effect of x-ray reflection within a channel is important for understanding the detection process on MCPs in the VUV region.