Author: Bayesteh, S.
Paper Title Page
MOPF06 Beam Profile Monitors at REGAE 212
 
  • H. Delsim-Hashemi, K. Flöttmann
    DESY, Hamburg, Germany
  • S. Bayesteh
    Uni HH, Hamburg, Germany
 
  A new linac is commissioned at DESY mainly as the electron source for femtosecond electron diffraction facility REGAE (Relativistic Electron Gun for Atomic Exploration). REGAE enables studies on structural dynamics of atomic transition states occurring in the sub-hundred femtosecond time-scale. REGAE comprises a photo-cathode gun followed by normal conducting 1.5 cell rf-cavity to provide sub pC electron-bunches of 2-5 MeV with a coherence length of 30nm. In order to produce and maintain such electron bunches, sophisticated single-shot diagnostics are desired e.g. emittance, energy, energy-spread and bunch-length measurement. REGAE rep-rate can be up to 50 Hz. This relatively high rep-rate makes it more challenging to deal with low intensity detection especially in single-shot mode. In this contribution the conceptual ideas, realization and results of transversal diagnostics will be presented.  
 
WEPF24 Charge Monitors at the Relativistic Electron Gun for Atomic Exploration – REGAE 868
 
  • H. Delsim-Hashemi, K. Flöttmann, M. Seebach
    DESY, Hamburg, Germany
  • S. Bayesteh
    Uni HH, Hamburg, Germany
 
  A new linac is commissioned at DESY mainly as the electron source for femtosecond electron diffraction facility REGAE (Relativistic Electron Gun for Atomic Exploration). REGAE comprises a photo-cathode gun followed by normal conducting 1.5 cell rf-cavity to provide sub pC charge electron-bunches of 2-5 MeV with a coherence length of 30nm. In order to produce and maintain such electron bunches, sophisticated single-shot diagnostics are desired e.g. emittance, energy, energy-spread and bunch-length measurement. There are three methods at REGAE for charge measurement. The most routine method is based on Faraday-cups that are distributed along machine and can provide charge reading down to ~50 fC. The second method, which is non-destructive, is a cavity based antenna that measures beam induced fields. A third method is based on beam-profile measurement diagnostics. By proper calibration of integral intensity that arrives at detector one can measure charges down to fC level. The last method has the potential to reach the limit of few electrons charge when state-of-the-art intensifiers are used in profile monitors.