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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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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

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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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g t( )

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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 + …