Design and application of multimegawatt X-band deflectors for femtosecond electron beam diagnostics

作者：Dolgashev Valery A^*; Bowden Gordon; Ding Yuantao; Emma Paul; Krejcik Patrick; Lewandowski James; Limborg Cecile; Litos Michael; Wang Juwen; Xiang Dao

来源：Physical Review Special Topics - Accelerators and Beams, 2014, 17(10): 102801.

DOI：10.1103/PhysRevSTAB.17.102801

Performance of the x-ray free electron laser Linac Coherent Light Source (LCLS) and the Facility for Advanced Accelerator Experimental Tests (FACET) is determined by the properties of their extremely short electron bunches. Multi-GeV electron bunches in both LCLS and FACET are less than 100 fs long. Optimization of beam properties and understanding of free-electron laser operation require electron beam diagnostics with time resolution of about 10 fs. We designed, built and commissioned a set of high frequency X-band deflectors which can measure the beam longitudinal space charge distribution and slice energy spread to better than 10 fs resolution at full LCLS energy (14 GeV), and with 70 fs resolution at full FACET energy (20 GeV). Use of high frequency and high gradient in these devices allows them to reach unprecedented performance. We report on the physics motivation, design considerations, operational configuration, cold tests, and typical results of the X-band deflector systems currently in use at SLAC.

• 出版日期2014-10-2