Extended Data Fig. 7: Electron-beam spectra detected at the exit of the undulators.
From: Free-electron lasing at 27 nanometres based on a laser wakefield accelerator
Energy spectra of electron beams for 200 consecutive shots detected with spectrometer 2. The average energy of the electron beam was estimated to be 485 MeV with energy fluctuations of 3.3% and a reproducibility of approximately 100%.
