Electron–photon scattering, or Thomson scattering, is one of the most fundamental mechanisms in electrodynamics, underlying laboratory and astrophysical sources of high-energy X-rays. After a century of studies, it is only recently that sufficiently high electromagnetic field strengths have been available to experimentally study the nonlinear regime of Thomson scattering in the laboratory. Making use of a high-power laser and a laser-driven electron accelerator, we made the first measurements of high-order multiphoton scattering, in which more than 500 near-infrared laser photons were scattered by a single electron into a single X-ray photon. Both the electron motion and the scattered photons were found to depend nonlinearly on field strength. The observed angular distribution of scattered X-rays permits independent measurement of absolute intensity, in situ, during interactions of ultra-intense laser light with free electrons. Furthermore, the experiment's potential to generate attosecond-duration hard X-ray pulses can enable the study of ultrafast nuclear dynamics.

中文翻译：

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高阶多光子汤姆逊散射

电子-光子散射或Thomson散射是电动力学中最基本的机制之一，是高能X射线的基础实验室和天体物理学来源。经过一个世纪的研究，直到最近，才有足够高的电磁场强度可用于在实验室中对汤姆森散射的非线性机制进行实验研究。利用大功率激光和激光驱动的电子加速器，我们首次进行了高阶多光子散射的测量，其中单个电子将500多个近红外激光光子散射为单个X射线光子 发现电子运动和散射光子都非线性地依赖于场强。原位，在超强激光与自由电子相互作用的过程中。此外，该实验产生亚秒级硬X射线脉冲的潜力可以使研究超快核动力学成为可能。