Simulation results of the FETS laserwire emittance scanner

The Front EndTest Stand (FETS) at Rutherford Appleton Laboratory (RAL) has been developed to demonstrate a high current (60 mA) H^- beam with the energy of 3 MeV that will be required for future proton drivers. Atsuch high power beam machine a non-invasive diagnostics is required. To measure the emittance of the ion beam a laserwire scanner is being developed. A low power laser will scan across the H^- ion beam. The H^-particles will be neutralized via a photo-detachment process producing a stream of fast neutral hydrogen atoms bearing information about the phase space distribution of the initial H^- beam. To design an effective detection system and optimize its parameters a simulation of the processes at the interaction point is required. W e present recent simulation results of the FETS laserwire system. Simulations were performed using measured data of the laser propagation and ion beam distribution, obtained with General Particle Tracer code.