First Tracking Studies of Phase Rotation Using a Scaling FFAG

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First Tracking Studies of Phase Rotation Using a
Scaling FFAG
Ajit Kurup BENE06 14th November
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Introduction

• A. Sato was kind enough to give me the OPERA
  field map of the PRISM magnet.
• Averaged the field map to use with ICOOL.
• First simulations in ICOOL with the coarse grid
  and without cavities.
• Obtain closed orbit and look at dynamic aperture.
• Include cavities and look at phase rotation.
• Use simple saw-tooth waveform for the rf with a
  gap size of 0.33m.
• Scale up B-field map for neutrino factory
  scenario.

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PRISM
The PRISM cavities are designed for 150-200 kV/m
at 5MHz. A simplified waveform is used in these
simulations.
For a 0.33m gap
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Field Map

• PRISM field map
• r from 565 to 735cm (step1cm)
• z from 0 to 17cm (step1cm)
• ? from -18o to 0o (step0.1o)
• Averaged field map
• r from 567.5 to 732.5cm (step5cm)
• z from 0 to 17cm (step1cm)
• ? from -17o to 0o (step1o)

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Dynamic Aperture

• Generated a beam evenly spaced in x, px, y and py
  for different momenta.
• xx0(-0.5m0.8m) in 0.1m steps, yy0 0.15m in
  0.03m steps
• pxpx00.02GeV/c in 0.005GeV/c steps
• pypy00.005GeV/c in 0.001GeV/c steps
• P P00.04GeV/c in 0.01GeV/c steps
• x0, y0, px0, py0 and P068MeV/c are the coords of
  the closed orbit particle.

For 10 turns of the ring
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Gaussian Beam Tracking

• Generated a Gaussian beam (with no correlations)
  of 1000 muons using
• ?x0.05, ?y0.025, ?px0.001 and ?py0.001
• P is fixed at 68MeV/c

For 3 cells
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Phase Rotation

• Generated a Gaussian beam (with no correlations)
  of 1000 muons using
• ?x0.05, ?y0.025, ?z0.0001, ?px0.001,
  ?py0.001 and ?pz0.034

For 7 turns of the ring
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Neutrino Factory Scenario

• Required momentum range is now 200 MeV/c 100
  MeV/c
• Scale field map by 200/68 2.94
• Keep everything else the same to start off with.
• First use a Gaussian generated beam then use beam
  from a mercury target simulation.

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Dynamic Aperture

• Generated a beam evenly spaced in x, px, y and py
  for different momenta.
• xx0(-0.5m0.8m) in 0.1m steps, yy0 0.15m in
  0.03m steps
• pxpx00.05GeV/c in 0.01GeV/c steps
• pypy00.012GeV/c in 0.002GeV/c steps
• P P0(-0.15 0.2)GeV/c in 0.05GeV/c steps
• x0, y0, px0, py0 and P00.2GeV/c are the coords
  of the closed orbit particle.

For 10 turns of the ring
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Gaussian Beam Tracking

• Generated a Gaussian beam (with no correlations)
  of 1000 muons using
• ?x0.05, ?y0.025, ?px0.01 and ?py0.005
• P is fixed at 200MeV/c

For 3 cells
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Phase Rotation

• Generated a Gaussian beam (with no correlations)
  of 1000 muons using
• ?x0.05, ?y0.025, ?z0.0001, ?px0.01 and
  ?py0.005 and ?pz0.1
• RF same as for the PRISM case.

For 7 turns of the ring
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Phase Rotation(2)

• Generated a Gaussian beam (with no correlations)
  of 1000 muons using
• ?x0.05, ?y0.025, ?z0.0001, ?px0.01 and
  ?py0.005 and ?pz0.1
• RF same as for the PRISM case but now gap size is
  0.033m.

For 7 turns of the ring
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Phase Rotation (3)

• 10GeV protons on a mercury target MARS14
  simulation.
• Produced by H. Kirk and includes capture
  solenoid.
• No muons survived 7 turns.

Selection Criteria No. of positive muons in input file
none 978
0.16ltplt0.24 GeV/c 177
pxlt0.02 GeV/c 154
pylt0.01 GeV/c 86
all 1
This muon only survives 4.5 turns.
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Conclusions and Plan

• Simulation method looks ok, results consistent
  with PRISM results.
• Transverse momentum spread of the input beam
  needs to be improved for the neutrino factory
  scenario.
• Redo simulations with a less coarse field map.
• Can get p20 for neutrino factory but need to
  increase rf gradient, also can go to higher
  frequency. Otherwise itll take longer for the
  rotation.
• Investigate injection and effect of alignment
  errors.