High DC injection voltage photocathode e-beam sources

Laser switched photocathode sources are typically used to produce trains of polarized electron bunches for high performance accelerators. This paper consid-ers two high brightness, high charge-per-bunch, e-beam injector approaches that utilize laser gated cath-odes followed by DC beam acceleration sections com-prised of 1-3 grading electrodes. The use of grading electrodes provides reliable high voltage standoff between the plates themselves and ground. In the rectilinear beam source case in particular, we found that the uniformity of the emitted current density can have a major effect on final beam emittance and brightness.