Author: Gessner, S.J.
Paper Title Page
TUPEA045 Self-Modulation and Hosing Instability of Slac Electron and Positron Bunches in Plasmas 1235
 
  • J. Vieira, N.C. Lopes
    Instituto Superior Tecnico, Lisbon, Portugal
  • E. Adli, S.J. Gessner, M.J. Hogan, S.Z. Li, M.D. Litos
    SLAC, Menlo Park, California, USA
  • Y. Fang
    USC, Los Angeles, California, USA
  • C. Joshi, K.A. Marsh, W.B. Mori, N. Vafaei-Najafabadi
    UCLA, Los Angeles, California, USA
  • P. Muggli
    MPI, Muenchen, Germany
  • O. Reimann
    MPI-P, München, Germany
  • L.O. Silva
    IPFN, Lisbon, Portugal
 
  Funding: This work has been partially supported by Humboldt Foundation.
The understanding of the self-modulation (SMI) and hosing (HI) instabilities is critical for the success of the upcoming proton driven plasma wakefield acceleration experiments at CERN*. The use of long SLAC electron and positron bunches provides the possibility of understanding experimentally the interplay between SMI and HI. In this work we perform particle-in-cell simulations with the code OSIRIS with parameters that will be available for experiments at SLAC in 2013. We show that the SMI of 20 GeV lepton bunches can grow and saturate in less than 15 cm. Up to 8 GeV energy gain/loss could be observed after a meter long plasma. The HI can also be effectively mitigated by seeding the SMI using bunches with short rise times**. We also show analytically and numerically that in the linear regime and after saturation of the SMI the HI can be suppressed by a plasma-BNS damping analogue. Several diagnostics that could be used in experiments to measure the SMI development and these effects are also explored.
*G. Xia et al., J. Plasma Phys., 1-7 (2012).
**J. Vieira et al., Phys. Plasmas 19, 063105 (2012).
 
 
TUPME020 Design of a TeV Beam Driven Plasma-wakefield Linear Collider 1613
 
  • E. Adli
    University of Oslo, Oslo, Norway
  • W. An, C. Joshi, W.B. Mori
    UCLA, Los Angeles, California, USA
  • J.-P. Delahaye, S.J. Gessner, M.J. Hogan, T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  • P. Muggli
    MPI, Muenchen, Germany
 
  Funding: This work is supported by the Research Council of Norway and U.S. Department of Energy under contract number DE-AC02-76SF00515.
A novel design of a 500 GeV c.m. beam-driven PWFA linear collider with effective accelerating gradient on the order of 1 GV/m and extendable in the multi-TeV energy range is presented. The main bunches collide in CW mode at several kHz repetition frequency. They are accelerated and focused with several GV/m fields generated in plasma cells by drive bunches with very good transfer efficiency. The drive bunches are themselves accelerated by a CW superconducting rf recirculating linac. We consider the overall optimizations for the proposed design, compare the efficiency with similar collider designs like ILC and CLIC and we outline the major R&D challenges.
 
 
TUPWA069 Longitudinal Phase Space Dynamics with Novel Diagnostic Techniques at FACET 1865
 
  • S.J. Gessner, E. Adli, F.-J. Decker, M.J. Hogan, T.O. Raubenheimer
    SLAC, Menlo Park, California, USA
  • A. Scheinker
    LANL, Los Alamos, New Mexico, USA
 
  Funding: Work supported [optional: in part] by the U.S. Department of Energy under contract number DE-AC02-76SF00515.
FACET produces high energy density electron beams for Plasma Wakefield Acceleration (PWFA) experiments. The high energy density beams are created by chirping the electron beam with accelerating sections and compressing the beam in magnetic chicanes. Precise control of the longitudinal beam profile is needed for the drive-witness bunch PWFA experiments currently underway at FACET. We discuss the simulations, controls, and diagnostics used to achieve FACET's unique longitudinal phase space.