Time-resolved emittance measurements of an excimer-laser-driven metal photocathode

The velvet cathode material of a 4-MeV, electron beam injector was replaced with a material cathode and driven by an ArF excimer laser. Time-resolved measurements of photoelectron current and effective cathode temperature were made. A streak camera and B-dot (magnetic field) probes were the primary diagnostics for the experiment. The streak camera determined effective cathode temperature in a single spatial dimension. Time-integrated photography was used to observe plasma information in the cathode region. The results will be used to ascertain the feasibility of long-pulse (75-ns) beam generation for injection into a linear induction accelerator.< >