Transcript 1.3GHz Large apperature bpm’s

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FFAG Workshop
Summary: FFAG
WORKSHOP
nonscaling electron model
muon FFAGs
C. Johnstone Fermilab
fermilab April 2005
FFAG Workshop
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fermilab April 2005
Electron Model
 Advanced understanding and full lattice
designs
 Linear field lattices: Berg, Koscielniak, Johnstone,
Keil, Trbojevic
 Isochronous lattices: G. Rees
 Full simulation, tracking and error analysis
 Meot – full simulation tools + fringe field ability
 Machida – alignment and field quality analysis
 Keil – error studies with MAD
FFAG Workshop
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fermilab April 2005
Electron Model Technical
Specifications
 Full ring
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Factor of 2 energy gain
Lattice choice: doublet min(cost+phase-slip)
Periodicity: 42 identical cells
Injection
 Injector: 8-35 MeV Daresbury Energy Recovery
Superconducting Linac (ERSCL)
 Injection energy: 8-12 MeV, 130 - 140/cell
 Extraction energy 16-24 MeV, 25  30 /cell
FFAG Workshop
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Electron Model Goals
fermilab April 2005
 POP of nonscaling FFAG accelerator (muon
accelerator demonstration – other applications?)
 Large momentum compaction-reduced apertures
 Multi-resonance crossing without correction
 Includes integer and half integer resonances
 Bucketless acceleration
 1 and 2 fixed points, 5-20 turns
 Transverse and longitudinal dynamics
 Under phase-slip conditions relative to rf
 Chromatic dependence of beta functions through
acceleration cycle
 Symmetric and asymmetric parabolic pathlengths
FFAG Workshop
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fermilab April 2005
Electron Model Magnet
Specifications
 Preliminary magnet design: permanent
magnet + trim coils (slot constraints)
 For 10 MeV injection
 Permanent dipole component of 1.5 kG
 Permanent quad component of ~4T/m
 Quad trim coil provides +/- 20%
 Variation in dipole component can be provided by
varying injection energy or side plate location
 Slot length: 10-12 cm
 PM/core length: 5-7cm
 Magnet spacing: 5-7 cm
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FFAG Workshop
fermilab April 2005
Electron Model Magnet
Dipole plus quad field lines
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FFAG Workshop
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fermilab April 2005
Electron Model Magnet Tolerances
 Good-field region: 5-20 turns
 1% gradient error at +/-5cm
 Thermally stable PM material
 8 cm allows injection/extraction? – no
special magnets in ring
 1Hz operation or less
 No cooling
 No eddy current problems
FFAG Workshop
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fermilab April 2005
Electron Model Diagnostics
 OTR foils + cameras:
 Transverse phase space profiles
 Bunch train 109/bunch
 Single bunch operation – checking
 Longitudinal distribution – streak camera
 Resistive wall monitor – verify beampipe size and
cut-off frequencies
 1.3 GHz BPMs
 Single and multi-bunch design
 Fit inside magnets
 ~20 micron resolution
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Fermilab Main Injector
bpm
FFAG Workshop
fermilab April 2005
FFAG Workshop
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fermilab April 2005
Electron Model RF specifications
 1.3 GHz to match Daresbury Linac
 Frequency variation to change fixed points
 21-25 cm straight required for installation
 About half of the 42 cells will have rf.
FFAG Workshop
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fermilab April 2005
What can we afford under a NEST
 ¼ of the ring or 10 cells (~0.5 million
Euros with 30% contingency)
 Requires design and engineering
contributions on part of participating
institutions.
 Fermilab will propose funding design and
possibly a prototype magnet to lab management
 Control system/operation – Daresbury
 Others
 Hardware contributions:
 Streak and CCD cameras, OTR assemblies…
 Inventory institutions
FFAG Workshop
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fermilab April 2005
What would a nonscaling arc
demonstrate
 Achieve high momentum compaction and
nonscaling optics
 Verify nonscaling lattice over the factor of two change in
energy—before building full ring!
 Prototype and get diagnostics operational
 Multi-bunch – single bunch operation
 Intensity dependence and other systematics
 Optics
 Beam-based alignment
 Beam-based field measurements
 Check variation of optics and orbits using variable
injection energy !!! fringe field characterization !!!
FFAG Workshop
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fermilab April 2005
International Collaborative Projects
 Role and contributions to PRISM?
 Proton FFAGs?
 Define working groups?
 Range of applications – medical group
 SBIR applications? Reactor FFAGs