Emittance measurements for the SLAC gun test facility

The requirement of a high brightness electron source for the proposed Linac Coherent Light Source (LCLS) project at SLAC has led to the development of the Gun Test Facility (GTF). The facility consists of a photocathode RF gun, emittance compensation solenoid, a single 3-meter SLAC S-band linac section, a single XK-5 klystron, low and high energy diagnostic sections and a cathode drive laser. In this paper, the specifications of the desired electron beam are discussed along with results of PARMELA simulations to determine the optimum laser pulse shape for minimum beam emittance. The diagnostics of the GTF are discussed and measurements are presented which were made at the SUNSHINE Facility at Stanford to develop the instrumentation to be used at the Gun Test Facility once it is operational. Future beam diagnostics are also discussed.