Source and Injector Design for Intense Light Ion Beams Including Space Charge Neutralisation

One of the major challenge in the design of the Low En- ergy Beam Transport (LEBT) section of the high intensity proton, Hand deuteron beam accelerators is to transport the beam from the ion source to the RFQ with minimizing the emittance growth. New PIC ray-tracing methods allows to design and sim- ulate the transport of high intensity beam in the LEBT systems of future accelerators like FAIR Proton Linac or IFMIF-EVEDA linacs. These techniques enable a precise prediction of the effect of residual gas ionisation and the consequent neutralisation of the large beam space charge on the beam emittances. The amount of space charge com- pensation along a high intensity LEBT section is crucial for the achievable beam quality at the exit of the section. An algorithm for adequate modelling of the compensation is presented. It includes the dynamic behaviour of the com- pensation as well as its dependence on the longitudinal and radial position along the beam line. The impact of this de- pendence on the beam quality and the source and LEBT design is presented.