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激光同步辐射光源的辐射条件 总被引:1,自引:1,他引:0
激光同步辐射光源是一种新型的X射线光源,它利用高强度激光与相对论电子束发生康普顿散射,从而在电子的运动方向上辐射出X射线.本文在考虑电子的反冲基础上,利用康普顿散射研究了激光同步辐射光源(LSS)辐射光子的精确波长和能量;同时发现,对于背散射情况,只有当种子激光的波长λ1大于电子的物质波波长λm时才能发生LSS辐射;最后给出LSS辐射的极值波长λ2max=h/(m0γv)和极值能量εc2max=βε3. 相似文献
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长期以来,惯性约束聚变(ICF)研究软X射线诊断科学仪器设备的元器件标定工作主要依赖同步辐射光源X射线辐射计量站进行。该类装置通常与用于开展ICF研究的大型激光装置分处两地,难以满足ICF研究软X射线元器件实时实地的标定应用需求。另外,由于同步辐射和ICF激光等离子体产生的X射线辐射特性存在较大差异,同步辐射计量站的标定结果事实上也不能完全反映元器件在ICF实验应用中的计量响应特性。本文首先介绍一种基于单光学元件的软X射线紧凑型无谐波光源单色化技术,以此为基础提出研制基于ICF激光等离子体X射线源的同源、同几何位形、双束比较校准的多能量通道光源单色化系统,用于ICF应用软X射线元器件的在线标定。新系统一方面可望满足ICF软X射线元器件实时实地的标定应用需求;另一方面,其提供的标定光束的技术特征将最大可能地接近ICF激光等离子体X射线辐射本身。配备相应的X射线二极管(XRD)和标准探测器之后,该系统将形成一套具有在线自校准功能的新型多通道δ能量响应软X射线能谱仪。 相似文献
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X射线具有短波长和强穿透能力,利用电子对X射线的散射能够研究材料和分子的精密内部结构。信号的质量高度依赖于X射线发射源。2009年,美国能源部下属的斯坦福线性加速器中心国家实验室建成世界上第一台具有原子分辨率能力的X射线自由电子激光设施(LCLS),从此X射线进入激光时代,人类所能使用的X射线的峰值亮度比最强的同步辐射X射线光源提高了100亿倍。文章简要介绍了X射线自由电子激光的发展历程、产生原理和特性,并结合具体实验研究对如何应用X射线激光研究生物学领域的分子结构和动态变化进行总结。 相似文献
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同步辐射光源是目前世界上最好的光源,用它测量EXAFS谱自然效果极好.然而由于它设备庞大而昂贵,无法普及到一般实验室.转靶X光机比同步辐射装置要简单和便宜得多,但这种光源的性能不如同步辐射,每次实验所需时间也长得多.本文要介绍的激光EXAFS谱仪是用激光打到金属靶上所产生的X射线脉冲作为光源,并用拍照的方法记录EXAFS谱.其设备更加简单和便宜,而且测得EXAFS谱所需时间极短.当然这种方法也有它的局限性和缺点,例如一般只适用于测量较轻元素的EXAFS谱.激光EXAFS谱仪的结构如图所示. 相似文献
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杜应超 陈寒 张鸿泽 高强 田其立 迟智军 张智 查皓 施嘉儒 颜立新 邱睿 程诚 杜泰斌 李任恺 陈怀璧 黄文会 唐传祥 《强激光与粒子束》2022,34(10):104010-1-104010-9
基于高亮度电子束与超短强激光相互作用的逆康普顿散射X/γ射线源具有单色性好、能量可调、偏振可控等特点,在核安全及核安保领域具有广泛的应用前景。清华大学将研制国际上首套能量达MeV的紧凑准单能伽马源装置并开展包括先进辐射成像、基于核共振荧光的物质分析检测等应用工作。给出该光源设计方案,以及针对其关键性能指标进行的优化及光源最终性能指标。目前已完成光源的设计,正在进行部件的加工采购,预计将于2023年启动装置的安装调试工作,于2025年完成项目的调试和验收。 相似文献
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随着激光和加速器技术的发展,激光场强度和粒子能量也有所提升,在高场强和高电子能量的条件下,电子与光子的汤姆孙散射过程将达到高度非线性状态,在这种状态下会发生多光子效应,即单个电子同时与多个光子相互作用并辐射一个高能光子,此过程通常称为多光子汤姆孙散射.当场强和粒子能量变得更高时,需要引入量子电动力学理论来解决极端光场物理中的动理学过程.近期,全球多台数拍瓦激光装置逐渐投入使用,激光等离子体相互作用中的此类效应会变得极其显著.而全光汤姆孙散射成为目前研究极端光场物理最佳的实验方案,因此,系统地研究全光多光子汤姆孙散射是本领域未来十年极其重要的方向.本文对近年来全光汤姆孙散射实验从单光子、低阶多光子到高阶多光子的研究进展进行了综述,并对其未来的发展方向进行了展望.另外,伴随着散射过程产生的准直高亮X/伽马射线,有望发展成为具有重要应用价值的紧凑型超亮高能光源. 相似文献
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A compact permanent‐magnet system for measuring magnetic circular dichroism in resonant inelastic soft X‐ray scattering 下载免费PDF全文
Jun Miyawaki Shigemasa Suga Hidenori Fujiwara Hideharu Niwa Hisao Kiuchi Yoshihisa Harada 《Journal of synchrotron radiation》2017,24(2):449-455
A compact and portable magnet system for measuring magnetic dichroism in resonant inelastic soft X‐ray scattering (SX‐RIXS) has been developed at the beamline BL07LSU in SPring‐8. A magnetic circuit composed of Nd–Fe–B permanent magnets, which realised ~0.25 T at the center of an 11 mm gap, was rotatable around the axis perpendicular to the X‐ray scattering plane. Using the system, a SX‐RIXS spectrum was obtained under the application of the magnetic field at an angle parallel, nearly 45° or perpendicular to the incident X‐rays. A dedicated sample stage was also designed to be as compact as possible, making it possible to perform SX‐RIXS measurements at arbitrary incident angles by rotating the sample stage in the gap between the magnetic poles. This system enables facile studies of magnetic dichroism in SX‐RIXS for various experimental geometries of the sample and the magnetic field. A brief demonstration of the application is presented. 相似文献
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T. Gog D. M. Casa I. Kuzmenko R. J. Krakora T. B. Bolin 《Journal of synchrotron radiation》2007,14(4):339-344
A differential pump assembly is introduced which can provide a windowless transition between the full atmospheric pressure of an in‐air sample environment and the high‐vacuum region of a synchrotron radiation beamline, while providing a clear aperture of approximately 1 mm to pass through the X‐ray beam from a modern third‐generation synchrotron radiation source. This novel pump assembly is meant to be used as a substitute for an exit vacuum window on synchrotron beamlines, where the existence of such a window would negatively impact the coherent nature of the X‐ray beam or would introduce parasitic scattering, distorting weak scattering signals from samples under study. It is found that the length of beam pipe necessary to reduce atmospheric pressure to below 10 mbar is only about 130 mm, making the expected photon transmission for hard X‐rays through this pipe competitive with that of a regular Be beamline window. This result is due to turbulent flow dominating the first pumping stage, providing a mechanism of strong gas conductance limitation, which is further enhanced by introducing artificial surface roughness in the pipe. Successive reduction of pressure through the transitional flow regime into the high‐vacuum region is accomplished over a length of several meters, using beam pipes of increasing diameter. While the pump assembly has not been tested with X‐rays, possible applications are discussed in the context of coherent and small‐angle scattering. 相似文献
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Selm R Winterhalder M Zumbusch A Krauss G Hanke T Sell A Leitenstorfer A 《Optics letters》2010,35(19):3282-3284
We demonstrate a scheme for efficient coherent anti-Stokes Raman scattering (CARS) microscopy free of nonresonant background. Our method is based on a compact Er:fiber laser source. Impulsive excitation of molecular resonances is achieved by an 11 fs pulse at 1210 nm. Broadband excitation gives access to molecular resonances from 0 cm(-1) up to 4000 cm(-1). Time-delayed narrowband probing at 775 nm enables sensitive and high-speed spectral detection of the CARS signal free of nonresonant background with a resolution of 10 cm(-1). 相似文献
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Elena Eggl Martin Dierolf Klaus Achterhold Christoph Jud Benedikt Günther Eva Braig Bernhard Gleich Franz Pfeiffer 《Journal of synchrotron radiation》2016,23(5):1137-1142
While large‐scale synchrotron sources provide a highly brilliant monochromatic X‐ray beam, these X‐ray sources are expensive in terms of installation and maintenance, and require large amounts of space due to the size of storage rings for GeV electrons. On the other hand, laboratory X‐ray tube sources can easily be implemented in laboratories or hospitals with comparatively little cost, but their performance features a lower brilliance and a polychromatic spectrum creates problems with beam hardening artifacts for imaging experiments. Over the last decade, compact synchrotron sources based on inverse Compton scattering have evolved as one of the most promising types of laboratory‐scale X‐ray sources: they provide a performance and brilliance that lie in between those of large‐scale synchrotron sources and X‐ray tube sources, with significantly reduced financial and spatial requirements. These sources produce X‐rays through the collision of relativistic electrons with infrared laser photons. In this study, an analysis of the performance, such as X‐ray flux, source size and spectra, of the first commercially sold compact light source, the Munich Compact Light Source, is presented. 相似文献
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考虑电子的反冲并利用康普顿散射,研究了激光同步辐射光源(LSS)辐射的光子波长、光子能量。结果表明,对于不同的γ,LSS辐射的光子波长和能量有不同的近似公式。当γ<<λ1/4λe时,LSS辐射的光子波长λ2≈λ1/4γ2,能量(εc2≈4γ2εc1;当γ>>λ1/4λe时,LSS辐射的光子波长λ2≈λe/γ,能量cε2≈m0γc2;结果表明,LSS辐射的条件是种子激光的波长λ1大于电子的物质波波长λm;LSS辐射的极值波长是λ2m ax=h/m0γv,极值能量是cε2m ax=βeε;本文后半部分提出了利用北京正负电子对撞机的强流高亮度电子束与激光的康普顿背散射产生单色γ射线的建议。 相似文献
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The 266-nm ultraviolet-beam generation of all-fiberized super-large-mode-area narrow-linewidth nanosecond amplifier with tunable pulse width and repetition rate 下载免费PDF全文
We report on a compact, stable, all-fiberized narrow-linewidth (0.045 nm) pulsed laser source emitting laser beam with a wavelength of 266 nm, and tunable pulse width and repetition rate. The system is based on all-fiberized nanosecond amplifier architecture, which consists of Yb-doped fiber preamplifiers and a super-large-mode-area Yb-doped fiber power amplifier. The fiber amplifier with a core of 50 μ is used to raise the threshold of the stimulated Brillouin scattering (SBS) effect and to obtain high output power and single pulse energy. Using lithium triborate (LBO) crystal and beta-barium borate (BBO) crystal for realizing the second-harmonic generation (SHG) and fourth-harmonic generation (FHG), we achieve 17 μJ (1.73 W) and 0.66 μJ (66 mW), respectively, at wavelengths of 532 nm and 266 nm and a repetition rate of 100 kHz with pulse width of 4 ns. This source has great potential applications in fluorescence research and solar-blind ultraviolet optical communication. 相似文献