Focus characterization at an X-ray free-electron laser by coherent scattering and speckle analysis

X-ray focus optimization and characterization based on coherent scattering and quantitative speckle size measurements was demonstrated at the Linac Coherent Light Source. Its performance as a single-pulse free-electron laser beam diagnostic was tested for two typical focusing configurations. The results derived from the speckle size/shape analysis show the effectiveness of this technique in finding the focus' location, size and shape. In addition, its single-pulse compatibility enables users to capture pulse-to-pulse fluctuations in focus properties compared with other techniques that require scanning and averaging.

Source: Journal of Synchrotron Radiation - April 14, 2015 Category: Physics Authors: Sikorski, M.Song, S.Schropp, A.Seiboth, F.Feng, Y.Alonso-Mori, R.Chollet, M.Lemke, H.T.Sokaras, D.Weng, T.-C.Zhang, W.Robert, A.Zhu, D. Tags: X-ray FEL speckle focusing research papers Source Type: research