Title :
Flat-beam RF photocathode sources for linear collider applications
Author :
Rosenzweig, J.B.
Author_Institution :
Dept. of Phys., California Univ., Los Angeles, CA, USA
Abstract :
Laser-driven RF photocathodes represent a recent advance in high-brightness electron beam sources. The author investigates a variation on these devices that was obtained by using a ribbon laser pulse to illuminate the cathode, yielding a flat beam ( sigma /sub x/>> sigma /sub y/) which has asymmetric emittances at the cathode proportional to the beam size in each transverse dimension. The flat-beam geometry mitigates space charge forces which lead to intensity-dependent transverse and longitudinal emittance growth, thus limiting the beam brightness. The fundamental limit on achievable emittance and brightness is set by the transverse momentum distribution and peak current density of the photoelectrons.<>
Keywords :
electron accelerators; electron sources; linear accelerators; photocathodes; RF photocathode sources; asymmetric emittances; beam brightness; beam size; flat beam; high-brightness electron beam sources; linear collider; longitudinal emittance growth; peak current density; ribbon laser pulse; space charge forces; transverse dimension; Brightness; Cathodes; Current density; Electron beams; Geometrical optics; Laser applications; Laser beams; Optical pulses; Radio frequency; Space charge;
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.1991.164845
