Author: Yocky, G.
Paper Title Page
WEOBS4 Improved Energy Changes at the Linac Coherent Light Source 1424
 
  • N. Lipkowitz, H. Loos, C.R. Melton, G. Yocky
    SLAC, Menlo Park, California, USA
 
  The user requirements and beam time scheduling of the LCLS imposes a demand for fast changes in machine energy across the entire operating range of 3.3-15 GeV (480-10000 eV). Early operational experience during LCLS commissioning revealed this process to be problematic and error-prone, sometimes requiring substantial re-tuning at each change. To streamline the process, a software tool has been developed to gradually ramp the machine energy while the beam remains on, allowing beam-based feedbacks to continue to work during the energy change. The tool has considerably improved the speed and reliability of configuration changes, and also extends the capability of the LCLS, allowing for slow scans of the FEL photon energy over a wide range. This poster presents the basic process, analysis of the performance gains, and possible future improvements.  
slides icon Slides WEOBS4 [62.503 MB]  
 
THP184 Tuning of the LCLS Linac for User Operation 2462
 
  • H. Loos, R. Akre, A. Brachmann, F.-J. Decker, Y.T. Ding, P. Emma, A.S. Fisher, J.C. Frisch, A. Gilevich, P. Hering, Z. Huang, R.H. Iverson, N. Lipkowitz, H.-D. Nuhn, D.F. Ratner, J.A. Rzepiela, T.J. Smith, J.L. Turner, J.J. Welch, W.E. White, J. Wu, G. Yocky
    SLAC, Menlo Park, California, USA
 
  Funding: This work was supported by U.S. Department of Energy, Office of Basic Energy Sciences, under Contract DE-AC02-76SF00515.
With the Linac Coherent Light Source (LCLS) now in its third user run, reliable electron beam delivery at various beam energies and charge levels has become of high operational importance. In order to reduce the beam tuning time required for such changes, several diagnostics and feed-forward procedures have been implemented. We report on improved lattice diagnostics to detect magnet, model, and diagnostics errors as well as on measurements of transverse RF kicks and static field contributions and corresponding correction procedures to facilitate beam energy changes.