Title :
Measurement of thermal emittance for a copper photocathode
Author :
Graves, W.S. ; DiMauro, L.F. ; Heese, R. ; Johnson, E.D. ; Rose, J. ; Rudati, J. ; Shaftan, T. ; Sheehy, B.
Author_Institution :
NSLS, Brookhaven Nat. Lab., Upton, NY, USA
Abstract :
Measurements of the thermal emittance of an electron beam produced by photoemission from the copper cathode of a high power RF cavity are presented. The RMS normalized emittance has been measured as a function of laser spot size, applied surface field, and polarization of the laser beam at normal incidence. Local field enhancement due to surface effects is found to increase the emittance substantially beyond that expected for a perfect planar surface
Keywords :
accelerator RF systems; accelerator cavities; copper; electron accelerators; electron beam focusing; free electron lasers; linear colliders; particle beam dynamics; photocathodes; photoemission; polarisation; Cu; RMS normalized emittance; applied surface field; copper cathode; copper photocathode; electron beam; high power radiofrequency cavity; laser beam polarisation; laser spot size; linear colliders; local field enhancement; normal incidence; perfect planar surface; photoemission; surface effects; thermal emittance; Cathodes; Copper; Electron beams; Laser beams; Photoelectricity; Polarization; Power measurement; Radio frequency; Size measurement; Surface emitting lasers;
Conference_Titel :
Particle Accelerator Conference, 2001. PAC 2001. Proceedings of the 2001
Conference_Location :
Chicago, IL
Print_ISBN :
0-7803-7191-7
DOI :
10.1109/PAC.2001.987332
