NonScaling FFAG Accelerators for the Neutrino Factory Proton Driver

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Non-Scaling FFAG Acceleratorsfor the Neutrino
FactoryProton Driver

• Alessandro G. Ruggiero
• Brookhaven National Laboratory
• NuFact06 - Irvine University, California -
  August 24-30, 2006

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Requirements

• Kinetic Energy 5 - 15 GeV 11.6 GeV
• Average Power 4 MW 4 MW
• Repetition Rate 50 Hz 50 Hz
• Number of Bunches 3 - 5 5
• Bunch Length (rms) 1 - 3 ns 2 ns
• Number of Protons 4.31 x 1013 per pulse
• Protons per Bunch 0.862 x 1013

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Architectures

• Rapid-Cycling Synchrotrons
• Super-Conducting Linacs
• FFAG (cyclotrons, RLA, microtrons, )
• SCL CEBAF
• Dog-Bone
• FFAG
• The case for a Non-Scaling FFAG
• A.G. Ruggiero, BNL Report C-A/AP/219, Oct. 2005
• also in proceedings of NuFact06, Frascati, June
  2005

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FFAG Accelerators for Proton Driver
The scheme allows flexibility of choice of
energy, intensity, rep rate. It can suit any
requirements for muon production and collection
FFAGs are Non-Scaling of about the same
circumference and similar structure, located in
the same enclosure. Bunch Compression is done in
the last ring at the end of acceleration.
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Three - FFAG Accelerator Rings (1)
A.G. Ruggiero, 1.5-GeV FFAG Proton Accelerator
for the AGS Upgrade, Invited Talk to
EPAC-04, July 6-11, 2004, Lucerne, Switzerland.
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Three - FFAG Accelerator Rings (2)
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Three - FFAG Accelerator Rings (3)
Injection Injection
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RF Frequency Power

MHz
MW

Injector Ring Low-Energy Ring High-Energy Ri
ng
turns
turns

MHz
MW
turns
turns
MW
MHz
turns
turns
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Injector Ring and Injection
RF Ion Source ?
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Lattice Parameters
Non-Scaling Lattice
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Lattice Functions
All Rings Linear Field Profile
Injection Extraction
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Tune Variation Radial Compactnesssame result
for all Rings
Half a Period
? (p - pinj) / pinj
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Linear Field Distribution (kG vs. cm)
Injector Ring High-Energy Ring
Low-Energy Ring
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Extraction and Targetting

• The Revolution Period at Extraction from the
  High-Energy Ring is T0 2.70 µs
• Beam Bunches are extracted individually every n
  turns
• Pulse Duration
• n 1 n T0 2.70 µs 10.80 µs
• 2 5.40 21.60
• 3 8.10 32.40
• 4 10.80 43.20
• 5 13.50 54.00

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Conclusions

• FFAG Accelerators for Neutrino Factories are
  feasible
• Issues
• Space Charge at Injection
• Multiple Resonance Crossing
• Injector Linac (400-MeV DTL or ????)
• Multi-turn Injection of H
• Magnet Feasibility
• Fast RF sweep (ferrite, RF power)
• Collimation
• Numerical Tracking
• Cost Estimate
• It is possible to raise the Repetition Rate --gt 1
  kHz
• or CW Mode of Operation (Harmonic Number
  Jump)