DC High Voltage Conditioning of Photoemission Guns at Jefferson Lab FEL

Journal Article · Tue Aug 04 00:00:00 EDT 2009 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.3215595· OSTI ID:21316859

Hernandez-Garcia, C; Benson, S V; Biallas, G; Bullard, D; Evtushenko, P; Jordan, K; Klopf, M; Sexton, D; Tennant, C; Walker, R; Williams, G ^[1]

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1. Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States)

DC high voltage photoemission electron guns with GaAs photocathodes have been used to produce polarized electron beams for nuclear physics experiments for about 3 decades with great success. In the late 1990s, Jefferson Lab adopted this gun technology for a free electron laser (FEL), but to assist with high bunch charge operation, considerably higher bias voltage is required compared to the photoguns used at the Jefferson Lab Continuous Electron Beam Accelerator Facility. The FEL gun has been conditioned above 400 kV several times, albeit encountering non-trivial challenges with ceramic insulators and field emission from electrodes. Recently, high voltage processing with krypton gas was employed to process very stubborn field emitters. This work presents a summary of the high voltage techniques used to high voltage condition the Jefferson Lab FEL photoemission gun.

• OSTI ID: 21316859
• Journal Information: AIP Conference Proceedings, Vol. 1149, Issue 1; Conference: 18. international spin physics symposium, Charlottesville, VA (United States), 6-11 Oct 2008; Other Information: DOI: 10.1063/1.3215595; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
ACCELERATOR FACILITIES
BEAM PRODUCTION
CEBAF ACCELERATOR
DIRECT CURRENT
ELECTRIC POTENTIAL
ELECTRON BEAMS
ELECTRON GUNS
ELECTRON SOURCES
FIELD EMISSION
FREE ELECTRON LASERS
GALLIUM ARSENIDES
KRYPTON
PHOTOCATHODES
PHOTOEMISSION
POLARIZED BEAMS