General Issues for a MultiMW driver

1
General Issues for a Multi-MW driver

• Get the right number of particles to the pion
  target at the right energy and rep rate.
• Low energy linac ion source 50mA, beam
  chopping (ISIS/CERN FETS)
• Acceleration, beam halo control
• Beam accumulation H? stripping, injection,
  control
• Bunch compression to 1ns for NF

2
Different Approaches

• Full energy linac, accumulator and compressor
  rings (R. Garoby)
• 200 MeV linac, RCS for accumulation,
  acceleration and compression (volunteer?)
• FFAG acceleration (A. Ruggiero)

3
Comment

• Target is arguably the most difficult part of the
  NF facility (c.f. SNS/ESS experience)
• Proton driver must take account of target
  limitations (shock, heating) in its choice of
  energy and the length and structure of the bunch
  train.
• Driver energy and target geometry determine
  pion/muon distribution and affect design of
  capture channel.
• There is a need to maximise the number of muons
  entering the accelerating system.
• Particularly close collaboration is therefore
  needed between driver, target and muon front-end
  groups to produce optimum operable system
  overall.
• Inevitably means compromises between all regions
  of study.

4
Questions

• Is 4 MW still the required beam power?
• Given a clean sheet, what is the optimum driver
  energy and optimum in terms of what?
• What does the target want in terms of proton
  pulses (number of bunches, spacing, frequency)?
• Which driver type (linac/RCS/FFAG) best meets
  these requirements?
• Whose proton driver comes nearest? Where should
  future studies be directed?
• Anything else?