EXTENDING THE DUTY CYCLE OF THE ISIS H − ION SOURCE, THERMAL CONSIDERATIONS

The ISIS H − ion source is currently being developed on the Ion Source Development Rig (ISDR) at Rutherford Appleton Laboratory (RAL) in order to meet the requirements for the next generation of high power proton drivers. One key development goal is to increase the pulse width and duty cycle, but this has a significant effect on ion source temperatures if no other changes are made. A Finite Element Analysis (FEA) model has been produced previously [1] and is used here to understand the steady state and dynamic thermal behaviour of the source, and to investigate the design changes necessary to offset the extra heating.