IN PHYSICS

The 1.5 cell standing wave rf photoinjector has been operated for the past several months using a copper cathode. The photoinjector drive laser produces ub 2 ps pulses of UV (A = 266 nm) light with up to 200 p~J/pulse which generates up to 3 nC of charge. The emittance of the photoinjector was measured as a function of charge, rf launching phase, and peak accelerating field. Also, the quantum efficiency and pulse lengths of the laser beam and the electron beam were measured. 1