Author: van der Geer, S.B.
Paper Title Page
TUPWO056 Modelling of the EMMA ns-FFAG Ring using GPT 1994
 
  • R.T.P. D'Arcy
    UCL, London, United Kingdom
  • J.K. Jones, B.D. Muratori
    STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
  • S.B. van der Geer
    Pulsar Physics, Eindhoven, The Netherlands
 
  EMMA (Electron Machine with Many Applications) is a prototype non-scaling Fixed-Field Alternating Gradient (ns-FFAG) accelerator whose construction at Daresbury Laboratory, UK, was completed in the autumn of 2010. The energy recovery linac ALICE serves as an injector for the EMMA ring, within an effective energy range of 10 to 20 MeV. The ring is composed of 42 cells, each containing one focusing and one defocusing quadrupole. Acceleration over many turns of the EMMA machine has recently been confirmed. In some cases the bunch will traverse upwards of 100 turns, at which point the effects of space-charge may be significant. It is therefore necessary to model the electron beam transport in the ring using a code capable of both calculating the effect of and compensating for space-charge. Therefore the General Particle Tracer (GPT) code has been used. A range of injection beam parameters have been modelled for comparison with experimental results and those of other codes. The simulated effects of space-charge on the tune shift of the machine are also compared with those expected from theory.