• M.J. Easton, M. Aslaninejad, S. Jolly, J.K. Pozimski
  Imperial College of Science and Technology, Department of Physics, London

The PAMELA project aims to design an ns-FFAG accelerator for cancer therapy using protons and carbon ions. For the injection system for carbon ions, an RFQ is one option for the first stage of acceleration. An integrated RFQ design process has been developed using various software packages to take the design parameters for the RFQ, convert this automatically to a CAD model using Autodesk Inventor, and calculate the electric field map for the CAD model using CST EM STUDIO. Particles can then be tracked through this field map using Pulsar Physics’ General Particle Tracer (GPT). Our software uses Visual Basic for Applications and MATLAB to automate this process and allow for optimisation of the RFQ design parameters based on particle dynamical considerations. Initial particle tracking simulations based on modifying the field map from the Front-End Test Stand (FETS) RFQ design have determined the best operating frequency for the PAMELA RFQ to be close to 200 MHz and the length approximately 2.3 m. The status of the injector design with an emphasis on the RFQ will be presented, together with the results of the particle tracking.

• S. Jolly, M.J. Easton, P. Savage
  Imperial College of Science and Technology, Department of Physics, London
• A.P. Letchford, J.K. Pozimski
  STFC/RAL, Chilton, Didcot, Oxon

A 4m-long, 324MHz four-vane RFQ, consisting of four coupled sections, is currently being designed for the Front End Test Stand (FETS) at RAL in the UK. Previous beam dynamics simulations, based on field maps produced with a field approximation code, provide a baseline for the new design. A novel design method is presented that combines the CAD and electromagnetic modelling of both the RFQ tank and the vane modulations with more sophisticated beam dynamics simulations using the General Particle Tracer code (GPT). This approach allows the full integration of the optimisation of the RFQ, based on beam dynamics simulations using a 3D EM-field map of the CAD model, with the design and manufacture of the RFQ vane modulations and RFQ tank. The design process within the Autodesk Inventor CAD software is outlined and details of the EM modelling of the RFQ in CST EM Studio are given. Results of beam dynamics simulations in GPT are presented and compared to previous results with field approximation codes. Finally, possible methods of manufacture based on this design process are discussed.