Musumeci P, Moody J T, Scoby C M, Gutierrez M S, Bender H A, Wilcox N S
Department of Physics and Astronomy, UCLA, Los Angeles, California 90095, USA.
Rev Sci Instrum. 2010 Jan;81(1):013306. doi: 10.1063/1.3292683.
Single shot diffraction patterns using a 250-fs-long electron beam have been obtained at the UCLA Pegasus laboratory. High quality images with spatial resolution sufficient to distinguish closely spaced peaks in the Debye-Scherrer ring pattern have been recorded by scattering the 1.6 pC 3.5 MeV electron beam generated in the rf photoinjector off a 100-nm-thick Au foil. Dark current and high emittance particles are removed from the beam before sending it onto the diffraction target using a 1 mm diameter collimating hole. These results open the door to the study of irreversible phase transformations by single shot MeV electron diffraction.
在加州大学洛杉矶分校的飞马实验室已获得使用250飞秒长电子束的单次衍射图样。通过将射频光注入器中产生的1.6皮库仑、3.5兆电子伏特的电子束散射到100纳米厚的金箔上，记录到了具有足够空间分辨率以区分德拜-谢乐环图样中紧密间隔峰的高质量图像。在将电子束发送到衍射靶之前，使用直径1毫米的准直孔去除束流中的暗电流和高发射度粒子。这些结果为通过单次兆电子伏特电子衍射研究不可逆相变打开了大门。
