Author: Iverson, R.H.
Paper Title Page
TUB03 FEL Overcompression in the LCLS 337
  • J.L. Turner, F.-J. Decker, Y. Ding, Z. Huang, R.H. Iverson, J. Krzywinski, H. Loos, A. Marinelli, T.J. Maxwell, H.-D. Nuhn, D.F. Ratner, T.J. Smith, J.J. Welch, F. Zhou
    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
Overcompression of the Linac Coherent Light Source (LCLS) x-ray Free Electron Laser (FEL) at the SLAC National Accelerator Center is studied. The studies and operational implications are summarized in this talk.
slides icon Slides TUB03 [4.493 MB]  
THP026 Design Study of LCLS Chirp-Control with a Corrugated Structure 748
  • Z. Zhang, K.L.F. Bane, Y. Ding, Z. Huang, R.H. Iverson, T.J. Maxwell, G.V. Stupakov, L. Wang
    SLAC, Menlo Park, California, USA
  • P. Frigola, M.A. Harrison, M. Ruelas
    RadiaBeam, Marina del Rey, California, USA
  The purpose of this paper is to investigate the use of flat metallic plates with small corrugations as a passive dechirper, studying its effects on beam dynamics. Similar systems have been tested in Pohang and Brookhaven at relatively low energies (~100 MeV) and with relatively long bunches (>1ps) [*,**]. Four meters of such a structure are being machined by Radiabeam Systems for use in the LCLS with a high energy and femtosecond electron beam. In this paper we use a field matching program to obtain the longitudinal and transverse wakes for the purpose of the LCLS dechirper design. In addition, we fit the longitudinal wake to simple functions, so that one can obtain the wake without resorting to the field matching program. Since the transverse wakes–both dipole and quadrupole wakes–are strong, we include beam dynamics simulations to find the tolerances for injection jitter and misalignment in the LCLS.
* P. Emma, et al. PRL 112, 034801
** M. Harrison, et al., NaPAc 2013, Pasadena, USA
THP033 Mechanical Design for a Corrugated Plate Dechirper System for LCLS 785
  • M.A. Harrison, P. Frigola, D.W. Martin, A.Y. Murokh, M. Ruelas
    RadiaBeam Systems, Santa Monica, California, USA
  • Z. Huang, R.H. Iverson, T.J. Maxwell, Z. Zhang
    SLAC, Menlo Park, California, USA
  Funding: This work is supported by Department of Energy grant number DE-SC0009550.
RadiaBeam Systems is developing a novel passive chirp removal system using corrugated plates as studied by Bane and Stupakov.* Following on from low-energy experiments at BNL-ATF,** RBS will install a much larger and powerful system for removing the chirp from the 3-GeV beams in the LTU section at LCLS. The larger plates will present new challenges in the areas of manufacturing and mechanical control. In this paper we review the requirements for the dimensions of the corrugated plates for proper operation and the infrastructure necessary for precisely placing the plates so as not to adversely disrupt the beam.
* K. Bane, et al "Corrugated Pipe as a Beam Dechirper," SLAC-PUB-14925, 2012
** Harrison, M., et al "Removal of Residual Chirp in Compressed Beams Using a Passive Wakefield Technique." NaPAC13, 2013