Author: Bohler, D.K.
Paper Title Page
Adaptive Feedback for Automatic Phase-Space Tuning of Electron Beams in Advanced XFELs  
  • A. Scheinker
    LANL, Los Alamos, New Mexico, USA
  • D.K. Bohler
    SLAC, Menlo Park, California, USA
  Particle accelerators are extremely complex having thousands of coupled, nonlinear components which include magnets, laser sources, and radio frequency (RF) accelerating cavities. Many of these components are time-varying. One example is the RF systems which experience unpredictable temperature-based perturbations resulting in frequency and phase shifts. In order to provide users with their desired beam and thereby light properties, LCLS sometimes requires up to 6 hours of manual, experience-based hand tuning of parameters by operators and beam physicists, during a total of 12 hours of beam time provided for the user. Even standard operational changes can require hours to switch between user setups. The main goal of this work is to study model-independent feedback control approaches which can work together with physics-based controls to make overall machine performance more robust, enable faster tuning (seconds to minutes instead of hours), and optimize performance in real time in response to un-modeled time variation and disturbances.