Author: Hayati, M.
Paper Title Page
Characterization of High-Brightness Electron Beams at the Frontiers of Temporal and Spatial Resolution  
  • R. Tarkeshian, T. Feurer, M. Hayati, Z. Ollmann
    Universität Bern, Institute of Applied Physics, Bern, Switzerland
  • T. Garvey, R. Ischebeck, E. Prat, S. Reiche, V. Schlott
    PSI, Villigen PSI, Switzerland
  • P. Krejcik
    SLAC, Menlo Park, California, USA
  • W. Leemans, R. Lehé, S. Steinke
    LBNL, Berkeley, California, USA
  We present two novel diagnostics to characterize high-brightness electron beams. The first technique, based on the tunnel ionization of a neutral gas by the intense (GV/m) self-field of the electron beam, can be used to measure the volumetric charge density of the beam, for example to reconstruct pulse durations shorter than few femtoseconds or to measure transverse beam sizes below the micron level. Experiments with sub-femtosecond unipolar self-field of electron beam, that approach the through-the-barrier tunneling times, could further deepen our understanding of quantum tunneling process. The second method can be used to streak electron beams with single cycle THz radiation concentrated in a micrometer gap of a resonant antenna, creating an enhanced electric near-field distribution. With this diagnostic one can measure with sub-femtosecond resolution the longitudinal duration, the slice emittance and energy spread of beams with energies up to tens of MeV. We show the validity of both methods with analytical calculations and particle-in-cell code simulations. We finally present practical implementation of both diagnostics at LCLS, in the XLEAP* experiment, and BELLA.
* X-Ray Laser Enhanced Altosecond Pulse Generation (XLEAP) For LCLS.