Fermilab, Proton Driver, PRISM/PRIME

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Fermilab, Proton Driver, PRISM/PRIME

• David Neuffer
• Fermilab
• FFAG05

2
IntroFermilab Future Plans (Oddone 9/05)

• (Tevatron shuts down 2009)
• First Priority ILC
• Global Study 1 year present to DOE (end of
  2006)
• IF favorable, push for near-term construction at
  Fermilab
• Second Priority protons
• Becomes high priority if ILC near-term not
  encouraged
• PROTON DRIVER 8 GeV, MW superconducting linac
• If ILC near-term, continue facility incremental
  upgrades
• Priorities are NUMI, NoVA,
• Some excess proton capacity for other experiments

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From Oddone P5 Talk (9/2005)
ILC
Proton Driver
Budget Required
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Proton Driver and Muon beams

• 8GeV Linac can produce streams of 1.51014 8GeV
  protons at 10Hz
• gt 1022 protons/year
• Neutrino Physics main goal
• But Only 1/15 of these needed for Main
  Injector/NUMI
• Are there muon beam experiments that could use
  this intensity ??
• Tertiary muon beams
• P X ? p
• p ? µ ?
• 10-2 µ/p ? 1020 µ/year or more
• (other experiments will also be possible)

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Primary Parameter List (Foster, March
2005 reference)
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Review of the PD/Linac Cost
(All costs in 2004 K) Linac
Project MS 229,779
Project SWF 89,118
Project Subtotal 318,897
GA (16.05 MS 30.35 Labor) 63,927
Project (incl. GA) 382,824
Contingency (30) 114,847
Total Cost 497,670
Davis Bacon labor shows up as MS GA rate
will be lower on large POs
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Proton Driver Parameters
8 GeV Superconducting LINAC
Energy
GeV
8
Particle Type
H- Ions, Protons, or Electrons
Rep. Rate
Hz
10
Active Length
m
671
Beam Current
mA
25
Pulse Length
msec
1
Beam Intensity
P / pulse
1.5E14
(can also be H-, P, or e-)
P/s
1.5E15
Linac Beam Power
MW avg.
2
MW peak
200
MAIN INJECTOR WITH 8 GeV LINAC
MI Beam Energy
GeV
120
MI Beam Power
MW
2.0
MI Cycle Time
sec
1.5
filling time 1msec
MI Protons/cycle
1.5E14
5x design
MI Protons/hr
P / hr
3.6E17
H-minus Injection
turns
90

MI Beam Current
mA
2250
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LFV m-A ? e-A can use high intensity
Desirable Beam Characteristics
Experiment I0/Im dT ns DT ms pm MeV Dpm/pm
m-A ? e-A m ? eg m ? eee me- ? m-e 1021 1017 1017 1016 lt 10-10 n/a n/a lt 10-4 lt 100 n/a n/a lt 1000 gt 1 n/a n/a gt 20 lt 80 lt 30 lt 30 lt 30 lt 5 lt 10 lt 10 12
tm 1014 lt 10-4 100 gt 20 30 lt 10
gm-2 EDM 1015 1016 lt 10-7 lt 10-6 lt 50 lt 50 gt 103 gt 103 3100 lt1000 lt 2 lt 2
But bunched beam is needed
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m-A ? e-A experiments
m-A ? e-A produces monoenergetic e- (105MeV)

• Next generation of m-A ? e-A experiments has been
  proposed
• MECO was to be based at BNL (DOE and NSF
  rejected)
• PRISM-PRIME based at KEK/JHF
• Could be hosted at FNAL proton driver ?
• m-e Conversion workshop
• Jan. 11-12 at BNL

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MECO expt. (BNL proposal rejected)
Superconducting Detector Solenoid (2.0 T
1.0 T)
Tracker
Muon Stopping Target
Superconducting Transport Solenoid
(2.5 T 2.1 T)
Muon Beam Stop
Crystal Calorimeter
Superconducting Production Solenoid (5.0
T 2.5 T)
Collimators
Time structure
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PRISM-PRIME (Y. Kuno et al.)

• High intensity pulsed proton beam (bunch length
  lt10ns)
• 100-1000Hz bunches producing p gt µ bunches
• Phase rotation with rf field ?p/p 20 ? 2

P 68 MeV/c 20
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PRISM rf-rotation
Pµ
P 68 MeV/c 20 ?t 12ns (5ns rms)
?p3.4
?p1.9
5-turns, 38 beam decay
6-turns, 44 decay
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Proton Beam requirements

• MECO experiment
• Requires pulses of 8 GeV protons (lt30ns long)
  every 1µs (1.4µs)
• Obtained by slow extraction of short bunches (in
  AGS)
• Design requires 4?1013 p/s, 1.5 ? 10-3 captured
  µs/proton
• 105 µ/pulse
• 6?1017 µ/year from 4 ?1020 p/year
• PRISM-PRIME experiment
• Requires proton pulses (lt10ns long) at 103/s
  (1ms)
• 4 ?1014 p/s (50GeV) 10-2 to 10-3 µs/proton
• Up to 1022 p/year, gt 1019 µ/year
• Single-turn extraction of short bunches (lt10ns)
• Up to 4?109 µ/pulse
• Both require pulsed beams, proton linac beam must
  be repackaged in an accumulator ring

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Recycler as accumulator ring ?

• 8GeV Linac produces 1ms pulses at 10 Hz
• H- injection into Recycler
• 1ms fills circumference
• (100 turns)
• Bunch beam into pattern required for expt.
• Harmonic 10 buncher for MECO, slow extraction
• Harmonic 100 buncher for PRIME, single bunch
  extraction

Circumference C2pRave 3320m
Momentum P 8.89 GeV/c
Rev. frequency, Period f0 T0 89.8 kHz 11 µs
Slip factor ?1/?2- 1/?t2 0.0085
Tunes ?x, ?y 25.4,24.4

But Recycler circumference is large 100ms may be
too short a time for bunching
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Space Charge Difficulty

• Space Charge tune shift
• Parameters Ntot1.5?1014,eN 20p mm-mrad
• MECO 30ns/1µs BF 0.03 ?d? 4 too large
• Reduce N to 1.5?1013 ?d? 0.4
• Reduce N to 0.4?1013 ?d? 0.1
• PRISM/PRIME 10ns bunches, 100/ring
• BF 0.1 ?d? 1.2 too large (but closer)
• Larger eN, smaller Ntot,
• Smaller circumference proton ring could be better

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Recycler Bunching (for PRISM)

• Harmonic 100 buncher (9MHz)
• Bunch for 0.1s
• (Vrf ramps to 140kV)
• Bunch lengths reduced to
• 5ns rms
• (Prism wants lt 10ns full width.)
• Could then extract bunches one at a time over
  0.1s
• Uses 1/2 the possible linac pulses (500 bunches/s
  for PRISM) (100 at 5Hz)

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Other potential proton storage schemes

• Accumulator or Debuncher (C 454m) after 2010
• Large aperture machines
• ?t ? 5
• Difficult to inject H- (must bend beam from
  Linac) (B lt 0.05T at 8 GeV, ? gt 600m)
• Could take debunched protons from Recycler or
  Main Injector(in 450m chunks)
• Bunch into pattern needed for experiments
• Bunching easier than Recycler
• New 8 GeV Storage Ring ??

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New 8 GeV Accumulator/buncher/stretcher

• FFAG
• Type FODO racetrack,
• Superferric arcs
• nonscaling
• H- injection into NewRing (10Hz)
• 700 turns
• d? 0.4 at BF0.15 (s1.5ns)
• Harmonic 42 buncher for PRISM, single bunch
  extraction (40ns spacing)
• Slow extraction, single bunch extraction modes

Circumference C2pRave 454m
Momentum P 8.89 GeV/c
rf frequency, Voltage H42 V0 26 MHz 1MV
Slip factor ?1/?2- 1/?t2 -0.02
Tunes ?x, ?y 6, 8
aperture a, b 3,2cm
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NewRing (P)
Proton Linac (H-)
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Fermilab w/o SRF linac proton driver

• NOW Linac?8 GeV Booster (C454m)
• Currently Limited by losses in Booster
• 5Hz 3 ? 1012/ pulse
• 15Hz, 5 ? 1012/pulse possible (0.1MW) (6?1013
  protons/s)
• NUMI, MiniBOONE, Tevatron p-source
• MiniBOONE will terminate soon ??
• Single turn extraction is 1.5?s
• For pulsed experiments, need a storage ring
• Can use Recycler, Accumulator, Debuncher?
• Future New 8 GeV Booster
• With 1 GeV linac ??
• larger apertures, larger injection energies,
  deeper tunnel (5?1013/ pulse ??)
• (1MW ??)
• With new storage ring

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Generic High intensity muon beam

• Detailed m source design does not exist
• Straw man design worked out for the front end
  of a n factory
• supported by MARS simulations (Ray et al.)
• Target capture solenoid drift (forward
  capture)

• 1.4 x 1022 protons/year at 8 GeV yields 3 x
  1021 muons/year.

Charged particle spectra at end of decay channel
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Summary

• Muon Beams from the Proton Driver could be
  enabled
• Potential muon beam facilities could be
  developed
• PRISM, etc. could be hosted
• More Detailed design needed
• Proton Collection
• Recycler .
• New Stretcher/Buncher ring ??
• Beam line(s)
• Experimental area(s)

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References

• W. Foster et al., Proton Driver
• http//tdserver1.fnal.gov/project/8GeVLinac/Design
  Study/
• W. Molson, The MECO Experiment to Search for
  ?-N?e-N with 10-17 Sensitivity, U. Va. Seminar,
  June 2004
• MECO
• RSVP Rare Symmetry Violating Processes
  (MECO-KOPIO) NSF proposal, October 1999.
• PRISM Working group
• An Experimental Search for the µ--e- Conversion
  Process at an Ultimate Sensitivity of the Order
  of 10-18 with PRISM, The Prime Working Group,
  Jan. 1, 2003.
• R. Ray D. Roberts, Proton Driver physics study

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Recycler Bunching for MECO

• Harmonic 10 buncher (0.9MHz)
• Barrierbucket rf
• Bunch for 1s
• (Vrf ramps to 30kV)
• Bunch lengths reduced to
• 50ns rms
• (MECO wants 30ns full width.)
• Could then extract bunches in slow extraction
  over 1s