Paper  Title  Page 

MOPD19  Vertical Orbit Excursion FFAGs  96 


Fixedfield strong focussing accelerators (FFAGs), in which the beam orbit moves with increasing momentum into higher field regions, have been widely studied. Less wellknown is that the central orbit does not need to move outwards with energy: it can move in any direction including the verticallymoving orbit discussed in this paper. This allows for a magnet design with a smaller magnetised volume for a larger total energy range. A vertical analogue to the scaling FFAG is defined and its dynamic aperture studied for the case of an energy booster to the 800MeV ISIS synchrotron at RAL with various possible lattices. 