Computer Simulations of a High-Current Proton Beam at the SILHI-LEBT

For the injection into the future proton LINAC for FAIR the ion source and the low energy beam transport system have to deliver a 100 mA proton beam with an energy of 95 keV at the entrance of the RFQ within an acceptance of 0.3 π mm mrad (norm., rms). A 2-solenoid focussing system is foreseen as an injection scheme into the rf-accelerator. The beam parameters of the SILHI ion source and the 2-solenoid low energy beam transport (LEBT) setup at CEA/Saclay fulfill these requirements. Therefore joint emittance measurements for various beam parameters have been performed at the end of the LEBT in 2005. This contribution presents the computer simulations of the ion source extraction and LEBT, which supplemented these measurements using the KOBRA3INP computer code in order to study the influence of space charge effects. These simulations have been performed for different solenoid settings and for different space charge compensation degrees.