Title :
SLC polarized beam source electron optics design
Author :
Eppley, K.R. ; Lavine, T.L. ; Early, R.A. ; Herrmannsfeldt, W.B. ; Miller, R.H. ; Schultz, D.C. ; Spencer, C.M. ; Yeremian, A.D.
Author_Institution :
SLAC, Stanford, CA, USA
Abstract :
A description is presented of the design of the beam-line from the polarized electron gun to the linac injector in the Stanford Linear Collider (SLC). The polarized electron source is a GaAs photocathode, requiring 10/sup -11/-torr-range pressure for adequate quantum efficiency and longevity. The photocathode is illuminated by 3-ns-long laser pulses. The quality of the optics for the 160-kV beam is crucial since electron-stimulated gas desorption from beam loss in excess of 0.1% of the 20-nC pulses may poison the photocathode. The authors´ design for the transport line consists of a differential pumping region isolated by a pair of valves.<>
Keywords :
electron optics; linear accelerators; polarisation; GaAs photocathode; SLC polarized beam source electron optics; beam loss; beam-line; differential pumping region; electron-stimulated gas desorption; linac injector; longevity; polarized electron gun; quantum efficiency; transport line; valves; Cathodes; Electron beams; Electron optics; Electron sources; Laser beams; Linear particle accelerator; Optical beams; Optical design; Optical polarization; Optical pulses;
Conference_Titel :
Particle Accelerator Conference, 1991. Accelerator Science and Technology., Conference Record of the 1991 IEEE
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-0135-8
DOI :
10.1109/PAC.1991.164837
