1] Deutsches Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany [2] The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany.
1] Deutsches Elektronen Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany [2] The Hamburg Centre for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany [3].
Sci Rep. 2014 Jun 10;4:5234. doi: 10.1038/srep05234.
We measured the coherence properties of the free-electron laser SACLA on a single shot basis at an X-ray energy of 8 keV. By analysing small-angle X-ray scattering speckle patterns from colloidal dispersions we found a degree of transverse coherence of βt = 0.79 ± 0.09. Taking detector properties into account, we developed a simulation model in oder to determine the degree of coherence from intensity histograms. Finally we calculated a coherence time of τc = 0.1 fs and a pulse duration of 5.2 fs which corresponds with previous predictions.
我们在 8keV 的 X 射线能量下，对自由电子激光 SACLA 进行了单次测量，以研究其相干特性。通过分析胶体分散体系的小角度 X 射线散射斑纹图样，我们发现横向相干度βt = 0.79 ± 0.09。考虑到探测器的性能，我们开发了一个模拟模型，以便从强度直方图中确定相干度。最后，我们计算出相干时间τc = 0.1fs 和脉冲持续时间 5.2fs，这与之前的预测结果相符。
