Particle Production in the MICE Beam Line

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Particle Production in the MICE Beam Line
Particle Production in the MICE Beam Line
The RD Effort Towards Neutrino Factory
The Muon Ionization Cooling Experiment
MICE is set up to build a section of ionization
cooling, place it in a muon beam and test it in a
variety of beam and optics configurations. An
affordable section of cooling providing 10
reduction of transverse emittance is placed in a
muon beam of 140 - 240 MeV/c. By measuring the
particles one by one the emittance can be
determined before and after the cooling channel
with a precision of one part per mil.
MICE Beam Line and Instrumentation
Time of Flight Stations Hodoscopes using fast
scintillator bars, read by PMTs at both ends,
arranged in 2 planes (X and Y for
better performances)
The experiment is located at STFC Rutherford
Appleton Lab (UK)
Aerogel Cherenkov Counters upstream
pion/muon/electron separation 2 containers of
aerogel radiator with different indices of
refraction (n 1.07, 1.12) 5 p.e. in each PMT
for beta1
Starting from a 300 MeV/c pion beam, we reduced
gradually the field until the momentum selected
corresponds to 100 MeV/c. At this momentum only
positrons can travel through the beam line.

• Turn downstream Quadrupoles OFF
• Start with 480 MeV/c proton momentum at B1.
• Tune Q1, Q2 and Q3 maximize rate in GVA2
• Scan dipole magnet B2 at various proton momentums
  414 MeV/c, 374 MeV/c, 322 MeV/c,and measure
  Pion and Proton rates
• The Time of flight technique is used to identify
  particles

Particle Accelerator Conference, May 2009,
Vancouver, Canada
Electron and Muon Content
Starting from a 300 MeV/c pion beam, we reduced
gradually the field until the momentum selected
corresponds to 100 MeV/c. At this momentum only
positrons can travel through the beam line.
Starting from a 300 MeV/c pion beam, we reduced
gradually the field until the momentum selected
corresponds to 100 MeV/c. At this momentum only
positrons can travel through the beam line.
a full implementation of MICE with GEANT4
(G4MICE) (below an example) allows simulation and
reconstruction of all steps of MICE. There is
also a simpler ICOOL implementation of MICE for
optimization The beam line also has a G4beamline
description and Turtle for optimizations
We have measured relative proton and pion rates
in the MICE beam line at 321MeV/c, 374 and 414
MeV/c. As expected, proton production drops
drastically when decreasing momentum and has all
but disappeared at 321 MeV/c. With this
particular layout of detectors, a good setting
was established at 321 MeV/c for producing a
pure positive pion beam for further studies.
Jean-Sebastien Graulich, University of Geneva