The Muon Ionization Cooling Experiment MICE

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The Muon Ionization Cooling Experiment (MICE)

• Introduction and Motivation
• Status of Subsystems
• Progress
• 6D Cooling Discussion
• Summary

Terry Hart for the MICE Collaboration, Illinois
Institute of Technology, Low Emittance Muon
Collider Workshop, April 24, 2008
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MICE Description

• Muon Ionization Cooling Experiment (MICE)
• International accelerator RD project to provide
  first demonstration of muon cooling
• Being built at Rutherford Appleton Laboratory
  (RAL) using muon beam generated from ISIS.
• One muon cooling lattice cell with detectors
  measuring muon beam emittance before and after
  cooling.
• Emittance reduction 10 for 200 MeV/c muons
• Emittance measurement absolute precision 0.1

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 2 of 25
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MICE Goals

• Demonstrate ability to design, engineer, and
  build section of cooling channel providing
  desired performance for neutrino factory
• Place it in muon beam and measure performance
• Demonstrate understanding of muon cooling process
  by validating simulation predictions with
  measurements
• Measure cooling with different
• Beam momenta
• Beam emittances
• Absorber materials.
• Magnetic configurations

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 3 of 25
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MICE Institutions

• UK
• Brunel University
• Cockcroft Laboratory
• Daresbury Laboratory
• Glasgow University
• Imperial College
• Liverpool University
• Oxford University
• RAL
• Sheffield University
• USA
• ANL
• BNL
• Fairfield University
• FNAL
• Illinois Institute of Technology
• Jefferson Laboratory
• LBL

• Bulgaria
• Sofia
• China
• ICST Harbin
• Italy
• INFN Milano
• INFN Napoli
• INFN Roma III
• INFN Trieste
• Japan
• KEK
• Kyoto
• Osaka University
• Netherlands
• NIKHEF
• Switzerland
• CERN
• DPNC, Geneva

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 4 of 25
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MICE at RAL
ISIS accelerator
MICE experimental hall
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 5 of 25
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ISIS Accelerator

• 800 MeV proton synchrotron
• Provides muon, neutron beams for studies of
  microscopic structure and dynamics of matter
• Beamline for MICE

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 6 of 25
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Muons for MICE
800 MeV protons in ISIS

• 800 MeV protons in ISIS collide with titanium
  target producing pions.
• Pions captured in 1st quadrupole triplet
• Two dipole magnets steer beam.
• Pions decay to muons captured in decay solenoid.
• Muon beam transport through
• 2nd and 3rd quadrupole triplets
• Lead diffuser

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 7 of 25
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MICE Beamline
MICE Beamline from ISIS
Decay Solenoid
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 8 of 25
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MICE Beamline CommissioningMarch 16 April 4

• 12,000 activations of MICE target into ISIS beam
• Simplified beamline of 2 dipole magnets
  successfully operated
• Transport of 480 MeV/c tracks demonstrated by
  scanning downstream dipole current while upstream
  dipole current was fixed.
• No quadrupoles or decay solenoid
• About 30 particles/target dip observed in
  downstream scintillator
• Cherenkov counters detected first pions in proton
  beam
• Massive protons too slow to produce Cherenkov
  light
• MICE control system successfully operated magnets
• MICE data acquisition system operational
• Record data from scintillators and Cherenkov
  counters
• Offline data analysis

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 9 of 25
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MICE Components
µ/? PID
Time of Flight Counters
Cherenkov Detector

• Time of Flight Counters set of crossed
  scintillator strips
• 60 ps resolution
• First set to be shipped to RAL after final
  testing at Milan
• Cherenkov Detector
• Two sets (n 1.07, 1.12)
• Shown in MICE beamline

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 10 of 25
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MICE Components
Emittance Measurement
Scintillating Fiber Trackers
Solenoid Magnets

• Solenoid Magnets 4 T axial magnetic field
• Confine muons in beamline
• Enable track transverse momentum measurements
• Trackers 10 stations of fibers read out in 3
  views
• Contain 42,000 fibers
• Read out by cryogenic Visible Light Photon
  Counters
• VLPCs kept at 7 K by cryostats

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 11 of 25
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MICE Components
Cooling - Absorbers
Liquid Hydrogen Absorbers

• Liquid Hydrogen absorbers
• - MIRAPRO (Japan) absorber body design.
• - 1st absorber body to KEK September, 2008
• Focusing Coils
• - Order set England
• - Delivery of 1st coil October, 2009

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 12 of 25
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MICE Components
Cooling, RF Cavities
RF Cavities

• 201 MHz Prototype RF Cavity
• - Testing at Fermilab
• - High electric field w and w/o B fields
• Coupling Coils
• - Fabrication in progress at ICST Harbin, China
• - Expected by end of 2009

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 13 of 25
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MICE Components
µ/e PID
Calorimeter
Time of Flight Counter

• Calorimeter has two components
• - Scintillating fibers embedded in lead
• - 10 layers of scintillator
• Prototypes built
• Completion around end of 2008

lead with scintillating fibers
10-layer scintillator detector
lead layer with light guides
Prototype scintillator layers
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 14 of 25
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Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 15 of 25
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Cooling Description

• Absorber reduces p and p- by ionization.
• Acceleration in RF cavity restores p to initial
  value.
• (p-/p)final lt (p-/p)initial results in reduced
  transverse emittance.

Initial Beam Absorber
RF cavity
Initial p, p- Reduce p, p-
Restore p
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 16 of 25
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Measuring Emittance
Emittance Measure of spreads of particle
positions and momenta with respect to ideal muon
path.
x
Cooling channel
z(t)
y
Measure 6 kinematic parameters for each particle
before and after cooling channel.
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 17 of 25
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Measuring Emittance
Emittance Measure of spreads of particle
positions and momenta with respect to ideal muon
path.
x
?in
?out
Cooling channel
z(t)
y
Form covariance matrix of (x, y, t, px, py, E) of
all particles in beam
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 18 of 25
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Measuring Emittance
Emittance Measure of spreads of particle
positions and momenta with respect to ideal muon
path.
x
?in
?out
Cooling channel
z(t)
y
Calculate emittances
longitudinal, transverse
transverse only equivalent to
4D for solenoid
Compare ?in with ?out
Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 19 of 25
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MICE and 6D CoolingHighlights from Chris Rogers
Thesiswww.astec.ac.uk/intbeams/users/rogers/thesi
s.pdf

• ?trans, ?long roughly separate for MICE.
• Measure ?trans, ?long at two tracker reference
  planes
• Inside edges of each tracker, 4.69 m from MICE
  center
• ?long, ?6D with time, energy measurements
• Time from ToF counters
• Energy from trackers

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 20 of 25
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Simulated MICE 6D Emittance Residual Distribution
Brown Raw Distribution Blue Distribution
corrected for (x, y, t, px, py, E)
covariance matrix Offset from
detector errors Width function of number
of events

• 100 samples, 1000 events each
• of Neutrino Factory like beam
• ?6D 10.3 mm from
• ?trans 6 mm
• ?long 0.1 ns (or 30 mm)

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 21 of 25
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6D Cooling at RAL

• 6D cooling steps
• Momentum/position correlation with dipole field
• ?long to ?trans with wedge absorber
• Transverse cooling
• Options at RAL
• Off axis MICE beam
• Tilt MICE solenoid coils
• MANX

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 22 of 25
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6D Cooling at RAL Off-axis MICE Beam

• Fringe field acts like dipole
• Low energy particles spin faster than high energy
  particles
• Looks impractical

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 23 of 25
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6D Cooling at RAL Tilt MICE Coils

• Tilted field acts like dipole
• Remount coupling coils to construct RFoFo-like
  lattice
• Issues
• Probably funded limited
• Possible remounting questions due to different
  forces
• Needs optics design

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 24 of 25
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Summary

• MICE demonstration of muon cooling important step
  for design of muon HEP experiments
• MICE in exciting and busy startup phase
• MICE expects full emittance measurement program
  by 2010.
• MICE, designed for 4D emittance reduction, will
  also measure 6D emittance.
• Modifications of MICE for 6D cooling under
  consideration

Terry Hart, Illinois Institute of Technology

MICE Low Emittance Muon Collider
Workshop April 24, 2008 25 of 25