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Project XProton Driver
David Neuffer
September 2011
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0utline
Introduction Proton Driver history Mission
Project X Overview 3GeV cw Linac
• multiple output options 38 GeV pulsed linac
• extension to 4MW for Neutrino Factory/ Muon Collider 38 GeV variations
FFAG Discussion
Introduction
Since ~1995, Fermilab has identified an upgrade for the 8GeV Booster as its next major accelerator project intensity, reliability, …
Various versions suggested ~2GeV linac +16 GeV RCS ? 8GeV 800MHz SRF linac ?
• Foster 1300 MHz (use ILC)
Project X ICD-1 configuration
• 8GeV pulsed SRF Linac• ~ILC SRF/• Use 8GeV Recycler
Too expensive for DoE?• 1MW 8GeV beam ?
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Sergei Nagaitsev,Univer.
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Project X mission and design (S. Nagaitsev et al.)
Mission goals1. Provide 8 GeV beam to Main Injector for 2MW+
NUMI/NOvA/DuSEL expts. 2. Provide high-intensity medium-energy beams for fundamental
process experiments3. Provide a platform that can be extended to neutrino factory/muon
collider applications (4MW ?)4. ADS, nuclear physics, …
CD-2 Centerpiece is 3GeV CW linac
Current Design Layout
3 GeV CW linac 650MHz rf 1ma, 3MW feeds experiments
and 38 GeV Linac
1300MHz “ILC” cavities
5% duty factor, 10Hz, 0.3MW
feeds Recycler/ Main Injector for DuSEL
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3 GeV CW Linac
38 GeV pulsed Linac
Project X vs. other facilities
Sergei Nagaitsev,Univer. of D0, May 5, 2011
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PSISNS
TRIUMF
ISIS
JPARC 2015
JPARC now
JPARC 2015
AGS
CERNPS
U70
Booster PIP
MI
NOVALANSCE
JPARC now
ESS Design
Project X
Project X
Booster now
PrX MI
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0.1 1 10 100
Bea
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ower
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Beam Energy (GeV)
Project X 3-GeV beam is cw
Key innovation is cw linac + rf splitter (like CEBAF) to serve many users
To form time structure add chopper at injector (162.5 MHz RFQ with 5ma
H-source ) • ~2×108/bunch
arbitrarily kick out individual bunches at 2.5 MeV
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1500MHz beam500MHz in each exp
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Chopping and splitting for 3-GeV experiments
Separation scheme
Ion source and RFQ operate at 4.2 mA -162.5MHz
75% of bunches are chopped at 2.5 MeV after RFQ
Transverse rf splitter
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Time, us
1 MHz pulses
10 MHz pulses
20 MHz pulses
0.75MW
0.75MW
1.5MW
40.6 MHz deflector
Linac Systems overview
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b=0.11 b=0.22 b=0.4 b=0.61 b=0.9
325 MHz2.5-160 MeV
b=1.0
1.3 GHz3-8 GeV
650 MHz0.16-3 GeV
Section Freq Energy (MeV) Cav/mag/CM Type
SSR0 (G=0.11) 325 2.5-10 18 /18/1 SSR, solenoid
SSR1 (G=0.22) 325 10-42 20/20/ 2 SSR, solenoid
SSR2 (G=0.4) 325 42-160 40/20/4 SSR, solenoid
LB 650 (G=0.61) 650 160-460 36 /24/6 5-cell elliptical, doublet
HB 650 (G=0.9) 650 460-3000 160/40/20 5-cell elliptical, doublet
ILC 1.3 (G=1.0) 1300 3000-8000 224 /28 /28 9-cell elliptical, quad
CW Pulsed
RFQ
162.5 MHzor 325
0-2.5MeV
650 MHz cavities,cryomodules
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Parameter LE650 HE650β_geom 0.61 0.9R/Q Ohm 378 638G-factor, Ohm 191 255Max. Gain/cavity (on crest) MeV 11.7 19.3
Acc. Gradient MV/m 16.6 18.7Max surf. electric field MV/m 37.5 37.3Max surf. magnetic field, mT 70 70Q0 @ 2°K 1010 1.5 2.0P2K max [W] 24 29
650 MHz: β=0.61 650 MHz: β=0.9
38GeV for Main Injector
38 GeV pulsed Linac or RCS (FFAG?)
want 2+ MW at 60/120 GeV/ for DuSEL/ NOvA/… 0.75/1.33s cycles ~26ms-ma/pulse too much for stripper?
Inject 6 ~4ms pulses into 8 GeV Recycler 10Hz Linac 0.6s transfer to Main Injector
~320 kW maximum output power
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0 2 4 6 8 10400
800
1.2 103
1.6 103
0 100 200 300400
800
1.2 103
1.6 103
T [K] T [K]
max T( ) 1449
min T( ) 547
t [ms] t [ms]
162.5 /325 MHz must be chopped to fit 50MHz rf for Main Injector ~3/5 bunches accepted
Injection requires “painting” to reduce foil hits and match into transverse acceptance
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0 1 2 3 4 5 6 7 8 9 102-
1-
0
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f t( )
g t( )
h t( )
t
Upgrade to 4MW (for NF/MC) ?
Upgrade cw Linac to 5ma 15 MW peak power run at 10% duty cycle
Increase pulsed linac duty cycle to ~10% 8GeV × 5ma × 10% = 4MW
Run at 15 Hz (6.7ms injection/cycle) matches NF/MC scenarios
Chop at 50% for bunching source/RFQ 10ma
Need Accumulator, Compressor to bunch beam
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Need 15/60 Hz bunches
Add Accumulator and Compressor Rings ~8GeV rings Accumulator captures and bunches
beam• 2×1014 p, h=4
Compressor: ¼ phase rotate to short bunch (combine onto target for MC)
Challenges stripping injection: foil melts ? Lattice design
• large acceptance, δp/p FMC lattice (Alexhin) FFAG ??
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Parameter Accumulator CompressorCircumference 300m 300mTransition γt 4.0 11.3Slip factor η=1/γt
2-1/γ2 0.051 -0.0032rf voltage Vrf 4.0kV 120kV bunches (h) 4 4
Accumulator: σ = 6.5m
From Linac: σ = 11m
Compressor: σ = 0.5m
Current Status
Proposal Development and R&D SRF development
325 MHz• Cavity design , construction tests
650 MHz MOU with Jlab for 2 b =0.6 cavities Order for six b = 0.9 cavities in industry partnerships with India
1300 MHz• ~ILC cavities and cryomodules
PXIE – Front End test stand ~First 10 MeV of linac (~40m) RFQ, Wide band Chopper
• + initial 325 MHz rf Workshops for Mission need
Construction status:
Still waiting for CD-0
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3 8 GeV Alternative?
Use 3GeV: ~cw 1ma injector avoid 5ma upgrade ?
3 8 GeV FFAG similar to IDS FFAG
Challenge to Workshop : Develop FFAG scenario for project X Leo Jenner, J. Pasternak will discuss options
Would like scenario that can: start with driver for Main Injector upgradeable to 4MW (15/60Hz)
• with bunch compression for NF/MC be clearly more affordable than 38 GeV Linac + rings + …
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