HEP03

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HEP03
Advanced Neutrino Beams
Rob Edgecock RAL
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Candidates.

• Conventional super beam

• Neutrino Factory

• Beta beam

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Outline

• Introduction
• Proton driver
• Target and capture
• Muon frontend
• Acceleration
• Storage ring
• Conclusions

• Emphasis on problems and RD to be done

• Discussion of options being considered

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Introduction

• Idea for a Neutrino Factory muon collider
• Concept of a muon collider Tinlot (1960),
  Tikhonin (1968), Budker (1969), Skrinsky
  (1971) Neuffer (1979)
• Many advantages over electron collider
• But.luminosity!
• Fast cooling technique ionisation cooling
  invented 1981 Skrinsky and Parkhomchuk
• Another problem.neutrino radiation!

Enough neutrinos to be a problem Must be enough
to do physics
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Muon Collider
Three stage scenario Neutrino Factory Higgs
Factory Muon Collider Recently, much interest in
Neutrino Factory alone. 5 different
layouts BNL CERN FNAL J-PARC RAL
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RAL Layout
RAL Neutrino Factory layout
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Proton Driver

• Main requirements 4 MW beam power 1 ns bunch
  length ?50Hz
• Two types Linac RCS
• Range of energies 2.2 to 50 GeV
• RD HIPPI

F1 GP
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Proton Driver
30 GeV Rapid Cycling Synchrotron in the ISR tunnel
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Proton Driver
CERN Super-conducting Proton Linac
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Most advancedJ-PARC
(0.77MW)
J-PARC Facility
JAERI_at_Tokai-mura (60km N.E. of KEK)
Construction 20012006 (approved)
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JHF
Plan to start in 2007
Kobayashi
1GeV n beam
Kamioka
JAERI (Tokaimura)
Super-K 22.5 kt
Hyper-K 1000 kt
0.77MW 50 GeV PS
4MW 50 GeV PS
( conventional n beam)
Phase-I (0.77MW Super-Kamiokande) Phase-II
(4MWHyper-K) Phase-I ? 200
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JHF Superbeam
Conventional neutrino beam
Kobayashi
Off-axis
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Target
Many difficulties enormous power density ?
lifetime problems pion capture
Stationary target
Replace target between bunches Liquid mercury
jet or rotating solid target
Proposed rotating tantalum target ring
CERN
RAL
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Liquid Mercury Tests
Tests with a proton beam at BNL.

• Proton power 16kW in 100ns Spot
  size 3.2 x 1.6 mm
• Hg jet - 1cm diameter 3m/s

0.0ms
0.5ms
1.2ms
1.4ms
2.0ms
3.0ms
Dispersal velocity 10m/s, delay 40?s
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Magnet Tests
Tests with a 20T magnet at Grenoble.
Mercury jet (v15 m/s)
B 0T
B 18T
Jet deflection Reduction in velocity Reduction in
radius
Smoothing
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Pion Capture
20T
1.25T
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Horn Capture
Current of 300 kA
p
To decay channel
Protons
B 0
Hg target
B?1/R
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Target Facility
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Pion Production Experiments
Data taking 2001-2002 Proton energy 2-15
GeV Targets H2-Pb 2, 5, 100 Xo X-section to
few Optimise beam energy and target material
for NF
The Hadron Production Experiment
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Pion Production Experiments
Data-taking 2003-200? Proton energy 5-120
GeV Targets NuMI Be, C, H2, N2, Be, C, Cu,
Pb Re-use existing detectors
Main Injector Particle Production Experiment
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Phase Rotation
Beam after drift plus adiabatic buncher Beam
is formed into string of 200MHz bunches
Beam after 200MHz rf rotation Beam is formed
into string of equal-energy bunches matched to
cooling rf acceptance
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Transverse Cooling

• Cooling ? gt10 increase in muon flux
• Existing techniques cant be used ? ionsation
  cooling

beam in

• Cooling is delicate balance

beam out
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Transverse Cooling

• Cooling cells are complex

• RD essential MuCool, MuScat and MICE

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Transverse Cooling

• Recent development ring coolers

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MuScat

• Measurement of muon multiple scattering only
  relevant data e- scattering, Russia, 1942
• Input for cooling simulations and MICE
• First (technical) run at TRIUMF summer 2000, M11
  beam

• Run2 April 2003

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MuCool

• Design, prototype, test all cooling cell
  components
• High beam-power test of a cooling cell
• Preparations for MICE

• NCRF cavities with sufficient gradient in
  multi-T fields
• Be windows
• Up to kW power deposition in absorbers
• Safety considerations
• Low non-absorber thickness in beam -
  Absorber windows - Safety windows - RF
  windows
• Cost effective design and construction

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MuCool
Absorber window development
200MHz cavity development
MuCool Test Area
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MuCool
Original area
Stage 2 construction
What it will look like when it is finished
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MICE
MICE
Muon Ionisation Cooling Experiment
SC Solenoids Spectrometer, focus pair,
compensation coil
Liquid H2 absorbers or LiH ?
201 MHz RF cavities
T.O.F. I II Pion /muon ID precise timing
Tracking devices He filled TPC-GEM (similar to
TESLA RD) or sci-fi Measurement of momentum
angles and position
T.O.F. III Precise timing
Electron ID Eliminate muons that decay
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MICE
Muon Acceleration

• Needs to be fast muon lifetime
• Needs to be a reasonable cost not linacs all
  the way
• Baseline Recirculating Linear Accelerators

• Other possibilitiesFFAGs VRCS

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MICE
FFAGs

• Fixed Field Alternating Gradient ? magnets not
  ramped

• Cheaper/faster RLAs/RCSs
• Large momentum acceptance
• Large transverse acceptance ? less cooling
  required!

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MICE
FFAGs
Proof Of Principle machine built and tested in
Japan. 50keV to 500keV in 1ms. 150MeV FFAG under
construction at KEK.
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MICE
FFAGs
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Staging in Japan
Staging
Physics outcomes at each stage

• High Power Proton Driver
• Muon g-2
• Muon Factory (PRISM)
• Muon LFV
• Muon Factory-II (PRISM-II)
• Muon EDM
• Neutrino Factory
• Based on 1 MW proton beam
• Neutrino Factory-II
• Based on 4.4 MW proton beam
• Muon Collider

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MICE
FFAGs
RD

• Injection and extraction
• Magnets 10-20 GeV ring (120m radius) 6T SC
• RF low frequency (6.5MHz), 1MV/m

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MICE
VRCS

• Fastest existing RCS ISIS at 50Hz ? 20ms
• Proposal accelerate in 37?s ? 4.6kHz
• Do it 30 times a second
• 920m circumference for 4 to 20 GeV

Combined function magnets 100micron laminations
of grain oriented silicon steel
18 magnets, ?20T/m Eddy currents iron 100MW ?
350kW Eddy currents cu 170kW RF 1.8GV _at_
201MHz 15MV/m Muons 12 orbits, 83 survival
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MICE
Storage Ring
Main requirement underground lab(s) at large
distances
Longyearbyen 3520km Pyhasalmi 2290km
Tenerife 2750km
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MICE
Conclusions

• Neutrino oscillations one of most important
  physics results
• Many new experiments conceived
• New beam neutrino facilities required -
  Superbeams - Neutrino Factory - Beta
  beams
• All require extensive RD
• For Neutrino Factory - proton
  driver - target - frontend (MuCool,
  MICE) - acceleration
• World Design Study (WDS1) planned