Betatron x-ray sources from laser-plasma accelerators reproduce the principle of a synchrotron at the millimeter scale. They combine compactness, femtosecond pulse duration, broadband spectrum, and micron source size. However, when produced with terawatt class femtosecond lasers, their energy and flux are not sufficient to compete with synchrotron sources, thus limiting their dissemination and its possible applications. Here we present a simple method to enhance the energy and the flux of betatron sources without increasing the laser energy. The orbits of the relativistic electrons emitting the radiation were controlled using density tailored plasmas so that the energetic efficiency of the betatron source is increased by more than one order of magnitude.

中文翻译：

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密度定制等离子体中来自激光-韦克菲尔德加速器的硬X射线

来自激光等离子加速器的Betatron X射线源在毫米级再现了同步加速器的原理。它们结合了紧凑性，飞秒脉冲持续时间，宽带频谱和微米源尺寸。但是，当用太瓦级飞秒激光器生产时，其能量和通量不足以与同步加速器光源竞争，从而限制了它们的传播及其可能的应用。在这里，我们提出一种简单的方法来增强电子感应加速器源的能量和通量，而不增加激光能量。发射辐射的相对论电子的轨道使用密度定制的等离子体进行控制，从而使电子感应加速器源的能量效率提高了一个数量级以上。