Physical Review Accelerators and Beams (Nov 2019)

Compact -300  kV dc inverted insulator photogun with biased anode and alkali-antimonide photocathode

  • C. Hernandez-Garcia,
  • P. Adderley,
  • B. Bullard,
  • J. Benesch,
  • J. Grames,
  • J. Gubeli,
  • F. Hannon,
  • J. Hansknecht,
  • J. Jordan,
  • R. Kazimi,
  • G. A. Krafft,
  • M. A. Mamun,
  • M. Poelker,
  • M. L. Stutzman,
  • R. Suleiman,
  • M. Tiefenback,
  • Y. Wang,
  • S. Zhang,
  • H. Baumgart,
  • G. Palacios-Serrano,
  • S. Wijethunga,
  • J. Yoskowitz,
  • C. A. Valerio Lizarraga,
  • R. Montoya Soto,
  • A. Canales Ramos

DOI
https://doi.org/10.1103/PhysRevAccelBeams.22.113401
Journal volume & issue
Vol. 22, no. 11
p. 113401

Abstract

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This contribution describes the latest milestones of a multiyear program to build and operate a compact -300 kV dc high voltage photogun with inverted insulator geometry and alkali-antimonide photocathodes. Photocathode thermal emittance measurements and quantum efficiency charge lifetime measurements at average current up to 4.5 mA are presented, as well as an innovative implementation of ion generation and tracking simulations to explain the benefits of a biased anode to repel beam line ions from the anode-cathode gap, to dramatically improve the operating lifetime of the photogun and eliminate the occurrence of micro-arc discharges.