Author: Jankowiak, A.
Paper Title Page
WG106
 Status and Perspectives of SRF Photoinjector Development for BERLinPro  
 
  • T. Kamps, W. Anders, R. Barday, A. Burrill, A. Jankowiak, J. Knobloch, O. Kugeler, A.N. Matveenko, A. Neumann, E. Panofski, M. Schmeißer, J. Völker
    HZB, Berlin, Germany
  • A. Ferrarotto, T. Weis
    DELTA, Dortmund, Germany
  • S.G. Schubert
    BNL, Upton, Long Island, New York, USA
  • V.I. Shvedunov
    MSU, Moscow, Russia
  • J. Teichert
    HZDR, Dresden, Germany
  • I. Will
    MBI, Berlin, Germany
  • E.N. Zaplatin
    FZJ, Jülich, Germany
  
  The energy recovery linac (ERL) test facility BERLinPro asks for an electron source delivering a beam with low emittance and high average current. The SRF photoinjector concept is a suitable candidate for such an ERL class electron source. After successful running of an SRF photoinjector with superconding Pb cathode we are now concentrating on the next stage of the R&D programme. The talk will present an overview of current and planned activities, related to GunLab, the gun test facility of BERLinPro, high QE photocathodes and additional test setups probing operational limits of photoinjectors.  
slides icon Slides WG106 [3.351 MB]  
 
WG504
 Field Emission Measurements on Flat Mo-substrates  
 
  • R. Barday, A. Burrill, A. Jankowiak, T. Kamps, C. Klimm, J. Knobloch, F. Siewert
    HZB, Berlin, Germany
  • S. Lagotzky, G. Müller
    Bergische Universität Wuppertal, Wuppertal, Germany
  
  Funding: Work supported by Bundesministerium für Bildung und Forschung and Land Berlin.
Bi-alkali antimonide K2CsSb is a baseline photocathode material for the production of a high brightness electron beam with high average current for future 4th generation multi-user light sources. The low beam emittance required for these projects demands very high field gradient on the photocathode surface, increasing the probability of enhanced field emission (EFE) in the superconducting gun cavity. Molybdenum can be used as a substrate to reduce the lattice mismatch with the cathode crystal. Therefore we have measured the EFE from a flat Mo sample by means of field emission scanning microscopy (FESM) up to 180 MV/m surface field (Es). First EFE (1 nA) was noticed at Es = 60 MV/m, but a strong emitter activation resulted in a finally lower EFE onset at Es = 46 MV/m. Local I(E) measurements have revealed Fowler-Nordheim behavior with enhancement factors of 10-70, however with a wide range of emitting areas (0.1 nm2 - 4300 μm2) which hint for adsorbate or oxide effects. Finally the located emission areas were investigated by SEM/EDX to identify the origin of the EFE. 		 
slides icon Slides WG504 [3.581 MB]