CERN Accelerating science

Article
Title	Ultra Low Emittance Electron Gun Project for FEL Application
Author(s)	Ganter, R ; Dehler, M ; Gobrecht, J ; Gough, C ; Ingold, G ; Leemann, S ; Paraliev, M ; Pedrozzi, M ; Raguin, J Y ; Rivkin, L ; Schlott, V ; Streun, A ; Wrulich, A F
Affiliation	(PSI, Villigen ETH, Zürich)
Publication	2004
In:	22nd International Linear Accelerator Conference, Lubeck, Germany, 16 - 20 Aug 2004, pp.657
Subject category	Accelerators and Storage Rings
Abstract	Most of the current 1Å Free-Electron Laser (FEL) projects are based on thermionic or photocathode guns aiming at an electron beam emittance of 0.5 to 1 mm·mrad. The design of a gun capable of producing a beam with an emittance one or two order of magnitude lower than the state of the art would reduce considerably the cost and size of such a FEL. Due to the recent advances in nanotechnologies and vacuum microelectronics, a field-emitter based gun is a promising alternative scheme. We present first measurements on commercial field emitter arrays as well as 3-D numerical simulations of the electron beam dynamics for typical bunch distributions generated from field emitters in realistic gun geometries. The design and some experimental results on a 500kV pulser is also presented.