In the span of a 100 year since the discovery of first x-rays by Roentgen that won him the first Nobel prize in physics, several types of radiation sources have been developed. Currently, radiations at extremely short wavelengths have only been accessed at synchrotron radiation sources. However, the current 3rd generation synchrotron sources can only produce x-rays of energy up to 60 keV and pulse lengths of several picoseconds long. But needs for shorter wavelength and shorter pulse duration radiations demanded by scientists to understand the nature of matter at atomic/molecular scale initiated the new scientific research for the production of sub-picosecond, hard x-rays. At the Lawrence Livermore National Laboratory, a Thomson x-ray source in the backscattering mode---a head-on collision between a high intensity Ti:Sapphire Chirped Pulse Amplification laser and a relativistic electron beam---called the PLEIADES (Picosecond Laser-Electron Inter-Action for the Dynamical Evaluation of Structures) laboratory has been developed. Early works demonstrated the production of quasi-monochromatic, femto-second long, hard x-rays. Initially reported x-ray flux was in the low range of 105--10 6 photons per shot.; During the early stage of PLEIADES experiments, 15 T/m electromagnet final focusing quadrupoles (in a triplet lattice configuration) were employed to focus the beam to a 40-50 mum spot-size. A larger focal spot-size beam has a low-density of electron particles available at the interaction with incident photons, which leads to a low scattering probability. The current dissertation shows that by employing a 560 T/m PMQ (Permanent-Magnet Quadrupole) final focus system, an electron beam as small as 10-20 mum can be achieved. The implementation of this final focus system demonstrated the improvement of the total x-ray flux by two orders of magnitude. The PMQ final focus system also produced small electron beams consistently over 30-100 MeV electron beam energy, which enabled the production of x-ray energy over 40-140 keV.; In this dissertation, the PLEIADES Thomson x-ray facility will be described in detail includes the 100 MeV linac and the FALCON laser system. Later, we will discuss the design, construction and implementation of the PMQ final focus system in the beamline. The measurement of electron beam parameters before and after the final focus system will be presented. The beam measurements at the interaction region were accomplished with the use of both OTR (Optical Transition Radiation) imaged by a CCD camera and the fast streak camera for respective spatial and temporal alignments. The theoretical analysis in "real beam" effects and spacetime beam jitter effects will be given to help understand the observations. A 3D simulation tool developed for x-ray data analysis was used to provide direct comparisons with the x-ray flux, spectrum distribution and transverse x-ray profile.
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机译：自从伦琴发现第一批X射线并获得第一项诺贝尔物理学奖以来的100年间，已经开发了多种类型的辐射源。当前，极短波长的辐射仅在同步加速器辐射源处被获取。但是，当前的第三代同步加速器源只能产生高达60 keV的X射线能量，脉冲长度只有几皮秒。但是，科学家们要求了解更短波长和更短脉冲持续时间的辐射，以了解原子/分子尺度上的物质的本质，这为产生亚皮秒级硬X射线产生了新的科学研究。在劳伦斯利弗莫尔国家实验室，汤姆森X射线源处于背向散射模式-高强度Ti：蓝宝石Chi脉冲脉冲激光与相对论电子束之间的正面碰撞-被称为PLEIADES（皮秒激光） -开发了用于结构动态评估的电子交互作用实验室。早期工作证明了准单色，飞秒长的硬X射线的产生。最初报道的X射线通量在每发105--10 6个光子的低范围内。在PLEIADES实验的早期阶段，使用了15 T / m的电磁体最终聚焦四极杆（三重晶格配置）将光束聚焦到40-50微米的光点尺寸。较大焦点尺寸的束具有与入射光子相互作用时可用的低电子粒子密度，这导致低散射概率。目前的研究表明，通过采用560 T / m PMQ（永磁四极杆）最终聚焦系统，可以实现小至10-20μm的电子束。该最终聚焦系统的实施证明了总X射线通量提高了两个数量级。 PMQ最终聚焦系统还连续产生超过30-100 MeV电子束能量的小电子束，从而产生超过40-140 keV的X射线能量。在本文中，将详细描述PLEIADES Thomson X射线设备，包括100 MeV直线加速器和FALCON激光系统。稍后，我们将在光束线上讨论PMQ最终聚焦系统的设计，构建和实施。将介绍最终聚焦系统之前和之后电子束参数的测量。相互作用区域的光束测量是通过同时使用由CCD相机和快速条纹相机成像的OTR（光学跃迁辐射）完成的，以实现各自的空间和时间对准。将对“真实光束”效应和时空光束抖动效应进行理论分析，以帮助理解这些观察结果。使用为X射线数据分析开发的3D模拟工具，可以与X射线通量，光谱分布和横向X射线轮廓进行直接比较。
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