2018/12/11 by Aliaksei Halavanau, Halavanau, Aliaksei, Franz-Josef Decker +7
Engineering · Physics and Astronomy · #Accelerator Physics (physics.acc-ph) #Advanced X-ray Imaging Techniques #Crystallography and Radiation Phenomena #FOS: Physical sciences #Particle Accelerators and Free-Electron Lasers
paper · pdf · doi:10.48550/arxiv.1812.04661
openalex publication_date 2018/12/11 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We show the feasibility of generating X-ray pulses in the 4 to 8 keV fundamental photon energy range with 0.65 TW peak power, 15 fs pulse duration, 9×10-5 bandwidth, using the LCLS-II copper linac and hard X-ray (HXR) undulator. Third harmonic pulses with 8-12 GW peak power and narrow bandwidth are also generated. High power and small bandwidth X-rays are obtained using two electron bunches separated by about 1 ns, one to generate a high power seed signal, the other to amplify it by tapering the magnetic field of the HXR undulator. The bunch delay is compensated by delaying the seed pulse with a four crystals monochromator. The high power seed leads to higher output power and better spectral properties, with >94% of the X-ray power being within the near transform limited bandwidth. We discuss some of the experiments made possible by X-ray pulses with these characteristics, like single particle imaging and high field physics.