Musumeci P, Cesar D, Maxson J
Department of Physics and Astronomy, UCLA, Los Angeles, California 90095, USA.
Struct Dyn. 2017 May 19;4(4):044025. doi: 10.1063/1.4983390. eCollection 2017 Jul.
In this paper, we study by numerical simulations a time-resolved MeV electron scattering mode where two consecutive electron pulses are used to capture the evolution of a material sample on 10 ps time scales. The two electron pulses are generated by illuminating a photocathode in a radiofrequency photogun by two short laser pulses with adjustable delay. A streak camera/deflecting cavity is used after the sample to project the two electron bunches on two well separated regions of the detector screen. By using sufficiently short pulses, the 2D spatial information from each snapshot can be preserved. This "double-shot" technique enables the efficient capture of irreversible dynamics in both diffraction and imaging modes. In this work, we demonstrate both modes in start-to-end simulations of the UCLA Pegasus MeV microscope column.
在本文中，我们通过数值模拟研究了一种时间分辨的兆电子伏特电子散射模式，其中两个连续的电子脉冲用于在10皮秒时间尺度上捕获材料样品的演化。这两个电子脉冲是通过用两个具有可调延迟的短激光脉冲照射射频光阴极产生的。样品之后使用条纹相机/偏转腔将两个电子束投影到探测器屏幕的两个充分分离的区域。通过使用足够短的脉冲，可以保留来自每个快照的二维空间信息。这种“双脉冲”技术能够在衍射和成像模式下有效捕获不可逆动力学。在这项工作中，我们在加州大学洛杉矶分校飞马座兆电子伏特显微镜柱的端到端模拟中展示了这两种模式。
